Course No. STCA Credits: 2 (1+1). Course Title: Introduction to Computer Applications. THEORY. S. No. Topic/Lesson. 1. Introduction to Computers. INTRODUCTION. A computer is a programmable machine designed to perform arithmetic and logical operations automatically and sequentially on the input. Input. • It is the process of capturing or acquiring the information, or it is the process of accepting data or information, by using input the computer can do any .
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Introduction to Computer. Computer. A computer is an electronic device, operating under the control of instructions stored in its own memory that can accept data. 4. Chapter 1 Introduction to Computers. A World of Computers. Computers are everywhere: at work, at school, and at home. As shown in Figure , people. PDF | 12+ hours read | On Jan 1, , Fred Mugivane and others published INTRODUCTION TO COMPUTER.
It can be slower to use than a CLI if you are an expert user. Training time can be reduced. IBM Skip to main content. A Webpage can contain text, graphics, animation,audio, and video. The systems analyst is a key partner with project managers and system developers. Businesses, called access providers, offerusers and organizations access to the Internetfree or for a fee.
For any business to succeed and gain a certain degree of competitive advantage in any market, they have to carry out extensive research about that target market and their competitors.
It is very important to know what your competitors are doing, this information can help you strategize your business and look unique in the eyes of the consumer. A computer can be used to make business research on the internet, the power of the internet is unmeasurable, because search engines like GOOGLE will give you insights in each and every market and company. Online analytical companies like Compete. Since accounts deals with facts and figures, it is very essential to use a computer during the accounting process, this reduces on human errors and it also helps business owners keep track of their businesses without any need of learning accounting rmmakaha gmail.
Computers make accounting look too simple, so any one can use programs like QuickBooks to balance and track inventory. Mobile computers like tablets and notebooks can be used to access accounting data remotely. Online QuickBooks software from companies like intuit.
A business can use a computer to create a business website. To create a beautiful company website, go to Themeforest.
You can use your website to market your services and products, reach more customers by integrating your website content with social media sites like facebook and twitter.
Creating and Editing of Business documents: You can also use Microsoft Excel spread sheet to organize data inform of figures. Spread sheets can help business owners manipulate decision variables and determine their impacts on outcomes like profits and sales.
Using a spread sheet, a business owner can have an accurate answer to a given question in minutes and can often glance at the whole financial image of the company on a single page. You can also use spread sheets to set a price for a proposed product. Transfer of information: In this lesson we have already seen that a computer can be used to store data, so this data can be moved across the company using a computer. Information can easily move from one level to another using an internal network or external network.
An internal network ensures that information is only shared within the company, so an infrastructure to move this data is created so that employees and business managers share data using their computers.
Yet for an external network, users will be in position to access data stored on company database using the internet, in most cases, companies set up websites which require users to login to access this data. One of the key factors which drive a business is communication. Computers can be used to accelerate the communication process within a business. It is very important to stay in touch with your customers and listen to their needs and demands, many small businesses are using electronic mail as a communication media to reach their customers and business partners.
Also computers can be used in virtual communication, in this process both parties need to install a virtual communication software like SKYPE on their computers and start communication through VIDEO, small rmmakaha gmail.
Office and Supply Management: On a daily basis, businesses deal with buying and selling of goods and services, a computer can be used to manage supplies and inventory efficiently. Companies like Intacct. This all process will help you maximize cost savings and also improve on capital efficiencies. You can as well use a computer to manage and track basic supplies in a business, these supplies can include papers, printer-ink, and other small supplies used on a daily basis in a business.
Human Resources Management: Computers can be used to manage, hire and interview new employees, today, many small businesses and human resource managers use the internet to find talented individuals. Human resource managers can use a computer to train new employees on how a business operates and also allocate tasks to each new employee. Business managers can use computers to monitor the performance of each individual at work, this process ensures that no employee misuses company facilities and time.
Requires Training: To some extent, this process is costly and it takes time. For example, if a small business owner wants to use Quickbooks to manage their accounts , they have to take off time and learn how Quickbooks works, or they will have to pay an extra fee to hire a Quickbooks expert to teach them.
Even though the end result is good, time and money will be spent during this process. Computer Crime: Computers are used to provide efficient ways for employees to share information, but at the same time employees with malicious intentions can use this opportunity to hack into the system to access private business information for their personal gains.
In most cases this information can be sold to business rivals, which is harmful to a business. Computer crime is on the rise and many small businesses have been victims of data loss. Some times employees or outsiders can modify computer programs to create false information or illegal transactions or install viruses to corrupt stored information. Require Additional Infrastructure: You also have to rmmakaha gmail. Replaces Human Labor: If a business decides to use computers to complete most difficult tasks, humans will not be much needed and this will cause job loss and unemployment.
Lets take a simple example in a Bakery business, electronic temperature sensors can be used to control and report room temperature in the baking room, in this case, the bakery will need only one person to monitor results on the computer from the baking room, if the temperature drops or rises, notifications will be sent to the computer and the controller will respond immediately.
This is a good technology for a business, because it will guarantee efficiency and quality, but it will also cut off so many people. Different tasks are performed automatically by using computers. It reduces the need of people and increases unemployment in society. Wastage of time and energy. Many people use computers without positive purpose. They play games and chat for a long period of time.
It causes wastage of time and energy. Young generation is now spending more time on the social media websites like Facebook, Twitter etc or texting their friends all night through smartphones which is bad for both studies and their health. And it also has adverse effects on the social life. Data Security. The data stored on a computer can be accessed by unauthorized persons through networks. It has created serious problems for the data security.
Computer Crimes. People use the computer for negative activities. They hack the credit card numbers of the people and misuse them or they can steal important data from big organizations. Privacy violation. The computers are used to store personal data of the people. The privacy of a person can be violated if the personal and confidential records are not protected properly.
Health risks. The improper and prolonged use of computer can results in injuries or disorders of hands, wrists, elbows, eyes, necks and back. The users can avoid health risks by using the computer in proper position. They must also take regular breaks while using the computer for longer period of time.
It is recommended to take a couple of minutes break after 30 minutes of computer usage. Impact on Environment. The computer manufacturing processes and computer waste are polluting the environment. The wasted parts of computer can release dangerous toxic materials.
Green computer is a method to reduce the electricity consumed and environmental waste generated when using a computer. It includes recycling and regulating manufacturing processes. The used computers must be donated or disposed off properly. You can easily calculate your expenses and income.
You can list all expenses in one column and income in another column. Then you can apply any calculation on these columns to plan rmmakaha gmail. There are also specialize software that can manage your income and expenses and generate some cool reports.
Different types of games are available. These games are a source of entertainment and recreation. Many games are available that are specially developed to improve your mental capability and thinking power. The owner of a company can check the work of the employees from home. He can control his office while sitting at home. They can watch movies, listen to songs, and watch videos download different stuff.
They can also watch live matches on the internet. Educational and informative websites are available to download books, tutorials etc. They can also share photos and videos with friends. These programs include text, graphics and sound. Audio and Video lectures are recorded on the CDs. CBT is a low cost solution for educating people. You can train a large number of people easily. The students can learn new skills at their own pace. They can easily acquire knowledge in any available time of their own choice.
Training time can be reduced. Training materials are interactive and easy to learn. It encourages students to learn the topic. Planning and timing problems are reduced or eliminated. The skills can be taught at any time and at any place.
It is very cost effective way to train a large number of students. Training videos and audios are available at affordable prices. The use of computer can reduce the time that is spent on preparing teaching material. It can also reduce the rmmakaha gmail. The use of multimedia projector and PowerPoint presentations has improved the quality of teaching. It has also helped the learning process. Computer plays the key role in this kind of learning. Many institutes are providing distance learning programs.
The student does not need to come to the institute. The institute provides the reading material and the student attends virtual classroom. In virtual classroom, the teacher delivers lecture at his own workplace. The student can attend the lecture at home by connecting to a network. The student can also ask questions to the teacher. The questions are marked by computer.
It minimizes the chance of mistakes. It also enables to announce the result in time. Businessmen are using computers to interact with their customers anywhere in the world. Many business tasks are performed more quickly and efficiently.
Computers also help them to reduce the overall cost of their business. Computer can be used in business in the following ways. Marketing applications provide information about the products to customers.
Computer is also used to manage distribution system, advertising and selling activities. It can also be used in deciding pricing strategies. Companies can know more about their customers and their needs and requirements etc. Many stock exchanges use computers to conduct bids. The stockbrokers perform all trading activities electronically. They connect with the computer where brokers match the buyers with sellers.
It reduces cost as no paper or special building is required to conduct these activities. These tasks may be Online appointments, payroll admittance and discharge records etc.
These systems can monitor pulse, blood pressure and body temperature and can alert medical staff about any serious situations. While job titles and descriptions vary by company, the main task of computer programmers is problem solving and development of systems solutions using the appropriate methodologies and techniques. Programmers often work on projects as a team, each team member assigned according to strength and ability.
By typing code in 2nd and 3rd level programming languages which are languages become more like words rmmakaha gmail. Once finished coding they compile the program into machine language so the computer can follow the set of instructions. What types of tasks are involved in Computer Programming?
In addition to writing new programs, computer programmers update and maintain existing programs. They test programs to ensure efficiency, accuracy, and to identify programming errors. Some of the tasks programmers might also do the following: The systems analyst is a key partner with project managers and system developers. Systems analysts define software requirements and specifications and guide program design and development. Depending on the level of responsibility and the particular job role involved, duties may also include: Analyzing problems in software development and guiding the rectification of faults in programs 2.
Analyzing software requirements and defining program parameters and specifications 3. Undertaking analysis of current software products and determining approaches which will improve their user interface, performance and integrity 4. Leading team members and third parties in client organizations in the integration of technological methodologies and components of projects 5.
Guiding the preparation of software manuals and guides 8. Improving the interface between systems users, the operating system and applications software 9. Conducting user requirements analysis to match customer needs to company products and services Assisting the sales force with pre-sales activity such as proposal preparation, systems demonstrations and presentations, particularly in relation to larger and more important clients.
The role includes developing and designing the database strategy, monitoring and improving database performance and capacity, and planning for future expansion requirements.
They may also plan, co-ordinate and implement security measures to safeguard the database. A database administrator may 1. Closely related jobs: Network Technician, Network Engineer, Website Administrator, Systems Administrator, Telecommunications Engineer In summary Network administrators provide operational support for and management of computer networks to ensure they run efficiently. The IT networks can range from internet and private networks to large communications networks.
Research — important area 1. Depending on the context, high computer performance may involve one or more of the following: The speed of the CPU 2. The size of the ram random access memory 3. The speed of the hard disk 4.
Hard disk space 5.
Multiple applications running on the computer 6. Type of graphic card 7. Defragmenting files 8. Data bus type and size. Clock rate. Cache presence and size. CD-ROM drives speed. MMX processors. The clock speed of the CPU is the frequency of which the processor executes instructions or the frequency by which data is processed by the CPU.
It is measured in millions of cycles per second or megahertz MHz. If the Clock speed of the CPU is fast then definitely the performance of the computer will be affected positively, in other words the computer will carry out processing functions at a faster pace.
The higher the generation, the better.
For example, because of high performance new features, Pentium 75 fifth generation with the clock rate 75 MHz will outperform DX which is the fourth generation CPU with the clock rate MHz. Another important feature is word size measured in bits. This is because the RAM has the capability of storing data that the computer is currently using, because of the fact that it is fast to retrieve data stored in the RAM.
With the definition above, a large RAM size will mean a faster computer performance and a smaller RAM size will result to slower computer performance. But note: The amount of RAM is also important. Today, advanced operating systems require at least 4 megabytes of memory just to boot up a computer. Using more than one application at a time requires at least 8 megabytes, and reasonable performance today calls for 16 megabytes or more.
The benefits of adding more RAM include letting you open more applications at the same time, and working with large files or documents. More memory may also make your machine run much faster. The quality of DRAM chips used in a memory module is the most important component in determining the overall quality and reliability of RAM.
So which chips to consider? This can provide dramatic performance improvements. However, at this time, EDRAM is scarce, very expensive and has not been adopted by many system vendors. The hard disk speed of different hard disks is not consistent because they vary by manufacturer, drive type and the use of the hard disk.
It therefore means that the higher the speed of the hard disk the faster the performance of the computer and vice versa. The smaller the space on the hard disk will result in a slower performance of the computer. The hard disk is filled with data this will use most of the memory leaving less memory for the operations of the processor. High-performance hard drives have at least 1.
You may be familiar with using a disk cache, such as Microsoft SmartDrive, which uses a small RAM buffer to speed up access to a large hard disk. This means that the more applications that are running the slower the rmmakaha gmail. Likewise if less or one application is running the performance of the computer will be faster.
So if a machine processes many graphics and it has a weak graphic card it will perform slower. This means that the more powerful the graphic card is the faster the performance of the computer. This will slow down the performance of the computer. The wider the data bus, the more information it can transfer. The Intel TM processor, for example, is able to execute many of its instructions in one clock cycle, while previous generations of Intel microprocessors require multiple clock cycles to execute a single instruction.
The Pentium processors have the ability to execute multiple instructions per clock cycle due to the fact that the Pentium processor's two pipelines can execute two instructions simultaneously.
If other modules of the system require more than one clock pulse, the CPU has to wait for them to keep up. This is called a wait state. The bigger the on-chip cache size, the better since more instructions and data can be stored on the chip, reducing the number of times the processor has to access slower, off- chip memory areas to get data.
Expanding secondary cache e. Otherwise look at octal or ten-speed technologies. The Pentium processor with MMX technology will give a better, smoother and more realistic multimedia experience. These processors have got 57 powerful new instructions specifically designed to manipulate and process video, audio and graphical data efficiently. However, your system will require software designed for MMX technology old software must be recompiled to take advantage of new MMX features.
Examples of Hardware are following: Software - Computer programs and related data that provide the instructions for telling computer hardware what to do and how to do it. Both of them must work together to make a computer produce a useful output.
Everything that a computer does, it acts under instructions written out as computer programs. The hardware needs these instructions to function.
Software is divided into two major types. System software are generally prepared by computer manufactures. These software products comprise of programs written in rmmakaha gmail. System software serves as the interface between hardware and the end users. System software is computer software designed to operate the computer hardware and to provide a platform for running application software.
The most basic types of system software are: It also provides a platform to run high-level system software and application software. In some publications, the term system software is also used to designate software development tools like a compiler, linker or debugger. Types of system software programs System software helps use the operating system and computer system.
It includes diagnostic tools, compilers, servers, windowing systems, utilities, language translator, data communication programs, database systems and more. The purpose of system software is to insulate the applications programmer as much as possible from the complexity and specific details of the particular computer being used, especially memory and other hardware features, and such accessory devices as communications, printers, readers, displays, keyboards, etc.
Specific kinds of system software include: Major development programs are language translators, programming tools and CASE [computer-aided software engineering] packages Features of system software are as follows: Electronic Spreadsheet and word processing programs or inventory or payroll programs. A computer-aided dispatch system is application software, as is each word processing program. Features of application software are as follows: Freeware may or may not have copyrights and may or may not have distribution restrictions.
If you decide to use it, you are expected to pay for the license. There is usually a disabling system in the program after a certain period of time i. Examples include rmmakaha gmail. Below is a basic list of the types of operating systems and a few examples of operating systems that fall into each of the types.
Many computer operating systems will fall into more than one of the below types. Examples of GUI operating systems are: Examples of operating systems that would fall into this category are: In preemptive multitasking, the operating system slices the CPU time and dedicates a slot to each of the programs.
Unix-like operating systems, e. Cooperative multitasking is achieved by relying on each process to provide time to the other processes in a defined manner.
Single-task A single-tasking system can only run one program at a time, while a multi-tasking operating system allows more than one program to be running in concurrency. This is achieved by time-sharing, dividing the available processor time between multiple processes that are each interrupted repeatedly in time slices by a task-scheduling subsystem of the operating system.
Single-user Single-user operating systems have no facilities to distinguish users, but may allow multiple programs to run in tandem. Time-sharing Time-sharing operating systems schedule tasks for efficient use of the system and may also include accounting software for cost allocation of processor time, mass storage, printing, and other resources to multiple users.
Distributed A distributed operating system manages a group of distinct computers and makes them appear to be a single computer. The development of networked computers that could be linked and communicate with each other gave rise to distributed computing. Distributed computations are carried out on more than one machine.
When computers in a group work in cooperation, they form a distributed system. Templated In an OS, distributed and cloud computing context, templating refers to creating a single virtual machine image as a guest operating system, then saving it as a tool for multiple running virtual machines. The technique is used both in virtualization and cloud computing management, and is common in large server warehouses. Embedded Embedded operating systems are designed to be used in embedded computer systems.
They are designed to operate on small machines like PDAs with less autonomy. They are able to operate with a limited number of resources. They are very compact and extremely efficient by design. Windows CE and Minix 3 are some examples of embedded operating systems. Real-time A real-time operating system is an operating system that guarantees to process events or data by a specific moment in time.
A real-time operating system may be single- or multi-tasking, but when multitasking, it uses specialized scheduling algorithms so that a deterministic nature of behavior is achieved. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts Library A library operating system is one in which the services that a typical operating system provides, such as networking, are provided in the form of libraries.
These libraries are composed with the application and configuration code to construct unikernels — which are specialized, single address space, machine images that can be deployed to cloud or embedded environments. Allows two or more users to run programs at the same time. Some operating systems permit hundreds or even thousands of concurrent users.
Supports running a program on more than one CPU. Allows more than one program to run concurrently. Allows different parts of a single program to run concurrently.
Real time: Responds to input instantly. Computers can operate in many different ways requiring different and complex operating systems. For example, the engine management system within a car uses a real time operating system in order to react to all the things going on within the engine. A real time operating system does not necessarily have to be fast.
It simply has to be quick enough to respond to inputs in a predictable way. Embedded computers often contain an RTOS as many are used to control something.
Another example of real time processing is computer games. For example, when an action is selected in a game, the data is fed back to the computer and the systems updated. The operating system switches jobs in and out of processor time according to priority.
For example, while one job is being allocated printer time, another will be being processed in memory. The processor is so fast that it seems that many jobs are being processed at the same time. Multi-tasking allows multiple tasks to run concurrently, taking turns using the resources of the computer. There are many variations on this basic theme, and the definition of multiprocessing can vary with context, mostly as a function of how CPUs are defined multiple cores on one die, multiple chips in one package, multiple packages in one system unit, etc.
However, the terms multitasking or multiprogramming are more appropriate to describe this concept, which is implemented mostly in software, whereas multiprocessing is more appropriate to describe the use of multiple hardware CPUs.
A system can be both multiprocessing and multiprogramming, only one of the two, or neither of the two. Generally, however, the processor is so fast that the response time at the most is a fraction of a second and the user feels they are being dealt with immediately.
Time-sharing systems are multi-user systems. However, the term "multitasking" is more common in this context. Another example uses multiple X Window sessions spread across multiple terminals powered by a single machine - this is an example of the use of thin client. Typically the processing of payrolls, electricity bills, invoices and daily transactions are dealt with this way. Jobs are stored in a queue until rmmakaha gmail. Often batch processed jobs are done overnight.
Operating System acknowledges the same, does the corresponding action and informs the operation by a display screen. It is capable of holding a number of computer systems networked together. VMS 32 bits X pre-emptive 9.
A boot sequence is the initial set of operations that the computer performs when power is switched on. The bootloader typically loads the main operating system for the computer.
Many microcomputer OS are single tasking, meaning they allow only one person to run one program at a time. Multitasking and multi-user OS permit more than one program to run and more than one person to use the system at one time. Multitasking OS may allow a user to receive a fax message at the same time one is searching a database. A task switching OS lets one load more than one program at a time and allows switching between the programs.
The task that one is working with is the foreground task and the suspended tasks are background tasks. Some of the most commonly used utilities on microcomputer OS are delete, copy contents of one diskette to another, format a diskette, delete files stored in a diskette, and compress data. An OS may be limited to running on specific hardware or may have versions that allow it to run on different types of computer systems.
See Interface section. The operating system is responsible for managing allocation of the processor between the different programs using a scheduling algorithm.
The type of scheduler is totally dependent on the operating system, according to the desired objective. The OS is responsible for managing the allocation of processor time to the different programs that will be using the computer. The processor can only execute one instruction at a time and in a multi-user system, conflicts are bound to arise when several user programs request usage of the processor at the same time.
The OS therefore allocates processor time to all users either in a round robin fashion or using a system of priorities. The operating system is responsible for managing the memory space allocated to each application and, where relevant, to each user. If there is insufficient physical memory, the operating system can create a memory zone on the hard drive, known as "virtual memory".
The virtual memory lets you run applications requiring more memory than there is available RAM on the system.
However, this memory is a great deal slower. The OS is responsible for managing the memory space allocated to each application. If there is insufficient physical memory the OS can create a memory zone on the hard drive known as virtual memory which lets you run applications requiring more memory than is available on the system. The operating system is responsible for the following activities in connections with memory management.
Keep track of which parts of memory are currently being used and by whom. Decide which processes to load when memory space becomes available.
Allocate and deallocate memory space as needed 3. The operating system is responsible for smooth execution of applications by allocating the resources required for them to operate.
This means an application that is not responding correctly can be "killed". The operating system is responsible for security relating to execution of programmes by guaranteeing that the resources are used only by programs and users with the relevantauthorizations.
The operating system manages reading and writing in the file system and the user and application file access authorizations. The OS manages reading from and writing to files and also controls the creation, manipulation and access to files. The operating system is responsible for the following activities in connections with file management: The operating system provides a certain number of indicators that can be used to diagnose the correct operation of the machine.
So that no parts of the computer system are idle for any significant period of time. Manage the accomplishment of the computing tasks of end users. It may involve multitasking capability where several computing tasks can occur at the same time. The computer displays a prompt, the user keys in the command and presses enter or return. This text-only interface contrasts with the use of a mouse pointer with a graphical user interface GUI to click on options, or menus on a text user interface TUI to select options.
Features of a command line interface include: In the early days of personal computers, all PCs used command-line interfaces. A GUI offers graphical icons, and visual indicators, as opposed to text-based interfaces, typed command labels or text navigation to fully represent the information and actions available to a user.
Figure shows an example of each of these categories ofsoftware, which are explained in the followingsections. System SoftwareSystem software consists of the programsthat control or maintain the operations of thecomputer and its devices. Two types of system software are the operatingsystem and utility programs. Operating System An operating system isa set of programs that coordinates all theactivities among computer hardware devices. It provides a means for users to communicatewith the computer and other software.
These parts ofthe operating system remain in memory whilethe computer is on. For example, you can use autility program to transfer digital photos to anoptical disc. Most operating systems includeseveral utility programs for managing diskdrives, printers, and other devices and media. You also can buy utility programs that allow youto perform additional computer managementfunctions. A widelyused type of application software related tocommunications is a Web browser, which allowsusers with an Internet connection to access andview Web pages or access programs.
Otherpopular application software includes wordprocessing software, spreadsheet software,database software, and presentation software. Many other types of application softwareexist that enable users to perform a varietyof tasks.
Software is available at stores that sell com-puter products Figure and also online atmany Web sites. Installing and Running ProgramsWhen purchasing software from a retailer, youtypically receive a box that includes an opticaldisc s that contains the program.
If you acquiresoftware from a Web site on the Internet, youmay be able to download the program; that is, theprogram transfers from the Web site to the harddisk in your computer. The instructions in software are placed onstorage media, either locally or online. To usesoftware that is stored locally, such as on a harddisk or optical disc, you usually need to install thesoftware.
Web applications that are stored online,by contrast, usually do not need to be installed. Installing is the process of setting up softwareto work with the computer, printer, and otherhardware. When you buy a computer, it usually hassome software preinstalled on its hard disk. Thisenables you to use the computer the first time youturn it on. To begin installing additional softwarefrom an optical disc, insert the program disc in anoptical disc drive and follow the instructions tobegin installation.
To install downloaded software,the Web site typically provides instructions for howto install the program on your hard disk. Figure Stores that sellcomputer productshave shelvesstocked withsoftware for sale. Who plays video games? The introduction of computer and video games thatcater to a broader audience has greatly increasedthe number of people who play them. According tothe Entertainment Software Association, approxi-mately 68 percent of the U.
Of these, 40 percent are women. Further,25 percent of Americans over 50 play video games,and the average game player is 35 years old. FAQ Introduction to Computers Chapter 1 17Once installed, you can run the program. Whenyou instruct the computer to run an installedprogram, the computer loads it, which means theprogram is copied from storage to memory. Oncein memory, the computer can carry out, or execute,the instructions in the program so that you can usethe program.
Figure illustrates the steps thatoccur when a user installs and runs a program. Tolearn more about starting and closing programs,complete the Learn How To 1 activity on page Step 1: INSTALLWhen you insert a program disc, such as a photoediting program, in the optical disc drive for thefirst time, the computer begins the procedure ofinstalling the program on the hard disk. Step 2: RUNOnce installed, you can instruct the computer torun the program.
The computer transfers instructionsfrom the hard disk to memory. Step 3: USEThe program executes so that you can use it. This program enables you to edit photos. How do I know if computer software will run on mycomputer? When writing instructions, a program-mer must be sure the program works properlyso that the computer generates the desiredresults.
Complex programs can require thou-sands to millions of instructions. Programmers use a programming language orprogram development tool to create computerprograms.
Figure shows some of theVisual Basic instructions a programmer maywrite to create a simple payroll program. Categories of ComputersIndustry experts typically classify computers inseven categories: Due to rapidlychanging technology, however, the distinctionamong categories is not always clear-cut.
Thistrend of computers and devices with technolo-gies that overlap, called convergence, leads tocomputer manufacturers continually releasingnewer models that include similar functionalityand features.
For example, newer cell phonesoften include media player, camera, and Webbrowsing capabilities. As devices converge, usersneed fewer devices for the functionality thatthey require.
When consumers replace outdatedcomputers and devices, they should dispose ofthem properly. Figure summarizes the seven categoriesof computers. The following pages discusscomputers and devices that fall in each category.
Then, rewrite the remaining false statements sothat they are true. A resource is a collection of computersand devices connected together viacommunications devices and transmissionmedia. Popular system software includes Webbrowsers, word processing software,spreadsheet software, database software,and presentation software. The Internet is one of the more popularservices on the Web. Two types of application software are theoperating system and utility programs.
To further check yourknowledge of pages 10 through 18, visitthe Computer Concepts CourseMate Website at www. Figure a Visual Basic programinstructions Figure b window appearswhen user runsprogram Theseshould be considered general guidelines only because of rapid changes in technology.
Personal ComputersA personal computer is a computer that canperform all of its input, processing, output,and storage activities by itself. A personalcomputer contains a processor, memory, andone or more input, output, and storage devices.
Personal computers also often contain acommunications device. The term, PC-compatible,refers to any personal computer based onthe original IBM personal computer design. PC andPC-compatible computers usually use aWindows operating system. Apple computersusually use a Macintosh operating system Mac OS. Two types of personal computers are desktopcomputers and notebook computers. Figure Apple computers, such as the iMac,usually use a Macintosh operating system.
In many models, the system unit is a talland narrow tower, which can sit on the floorvertically — if desktop space is limited. Some desktop computers function as a serveron a network. Others, such as a gaming desktopcomputer and home theater PC, target a specificaudience.
The gaming desktop computer offershigh-quality audio, video, and graphics with opti-mal performance for sophisticated single-user andnetworked or Internet multiplayer games. These high-end computerscost more than the basic desktop computer. Another expensive, powerful desktop computeris the workstation, which is geared for work thatrequires intense calculations and graphics capa-bilities.
An architect uses a workstation to designbuildings and homes. A graphic artist uses aworkstation to create computer-animatedspecial effects for full-length motion picturesand video games.
Mobile Computersand Mobile DevicesA mobile computer is a personal computeryou can carry from place to place. Similarly,a mobile device is a computing device smallenough to hold in your hand. The most popular type of mobile computeris the notebook computer. The followingsections discuss the notebook computer andwidely used mobile devices. Notebook ComputersA notebook computer, also called a laptopcomputer, is a portable, personal computer oftendesigned to fit on your lap.
Notebook computersare thin and lightweight, yet they can be as pow-erful as the average desktop computer. A netbook,which is a type of notebook computer, is smaller,lighter, and often not as powerful as a traditionalnotebook computer.
Most netbooks cost less thantraditional notebook computers, usually only afew hundred dollars. An ultra-thin is another typeof notebook computer that is lightweight andusually less than one-inch thick.
Some notebookcomputers have touch screens, allowing you tointeract with the device by touching the screen,usually with the tip of a finger. On a typical notebook computer, the keyboard ison top of the system unit, and the monitor attachesto the system unit with hinges Figure Thesecomputers weigh on average from 2. Most notebook computerscan operate on batteries ora power supplyor both. Are PCs or Apple computers more popular? While PCs still are more popular than Apple computers, Apple computer saleshave been rising consistently during the past few years.
In fact, Apple com-puter sales now account for more than 20 percent of all computer sales in theUnited States, with that number estimated to grow for the foreseeable future. FAQ Does the term, workstation, havemultiple meanings? In the computer industry, a workstation can be ahigh-powered computer or a client computer on a network. In an office environment, a workstation can refer to a workarea assigned to an employee. FAQ optical disc driveFigure On a typical notebook computer, the keyboard ison top of the system unit, and the display attaches to the systemunit with hinges.
Introduction to Computers Chapter 1 21Tablet PCs Resembling a letter-sized slate,the Tablet PC, or tablet computer, is a spe-cial type of notebook computer that you caninteract with by touching the screen with yourfinger or a digital pen. A digital pen looks like asmall ink pen but uses pressure instead of ink. Users write or draw on a Tablet PC by pressinga finger or digital pen on the screen, and issueinstructions by tapping on the screen.
Onedesign of Tablet PC, called a convertible tablet,has an attached keyboard. Another design,which does not include a keyboard, is calleda slate tablet Figure and provides othermeans for typing. Some Tablet PCs also sup-port voice input so that users can speak intothe computer. Tablet PCs are useful especially for takingnotes in lectures, at meetings, conferences, andother forums where the standard notebookcomputer is not practical.
Mobile DevicesMobile devices, which are small enoughto carry in a pocket, usually do not have diskdrives. Instead, these devices store programsand data permanently on special memoryinside the system unit or on small storagemedia such as memory cards. You often canconnect a mobile device to a personal computerto exchange information between the computerand the mobile device.
Some mobile devices are Internet-enabled,meaning they can connect to the Internetwirelessly. With an Internet-enabled device,users can chat, send e-mail and instant mes-sages, and access the Web. Because of theirreduced size, the screens on mobile devicesare small, but usually are in color. Popular types of mobile devices are smartphones and PDAs, e-book readers, handheldcomputers, portable media players, and digitalcameras.
Smart Phones and PDAs Offering theconvenience of one-handed operation, a smartphone Figure is an Internet-enabledphone that usually also provides personalinformation management functions such asa calendar, an appointment book, an addressbook, a calculator, anda notepad. In additionto basic phone capa-bilities, a smart phoneallows you to send andreceive e-mail messagesand access the Web —usually for an additionalfee. Some smart phonescommunicate wirelesslywith other devices orcomputers.
Many alsofunction as a portablemedia player and includebuilt-in digital camerasso that you can sharephotos or videos withothers as soon as youcapture the image.
Many smart phonesalso offer a variety ofapplication softwaresuch as word processing,spreadsheet, and games,and the capability ofconducting live videoconferences. Many smart phoneshave keypads that con-tain both numbers andletters so that you canuse the same keypadto dial phone numbersFigure The iPad is a widely used slate tablet.
Figure Some smart phones have touchscreens; others have mini keyboards. Others have a built-in minikeyboard on the front of the phone or a key-board that slides in and out from behind thephone.
Some have touch screens, where youpress objects on the screen to make selectionsand enter text through an on-screen keyboard. Others include a stylus, which is similar to adigital pen but smaller and has less functionality.
Types of messages users sendwith smart phones include text messages, instantmessages, picture messages, and video messages. A phone that can send picturemessages often is called a camera phone. A phone thatcan send video messages often is called avideo phone. A PDA personal digital assistant , which oftenlooks like a smart phone, provides personalinformation management functions such as acalendar, an appointment book, an address book,a calculator, and a notepad.
A PDA differs froma smart phone in that it usually does not providephone capabilities and may not be Internet-enabled, support voice input, have a built-incamera, or function as a portable media player. As smart phones and PDAs continue a trendof convergence, it is becoming increasingly dif-ficult to differentiate between the two devices. This has led some manufacturers to refer toPDAs and smart phones simply as handhelds.
E-Book Readers An e-book reader shortfor electronic book reader , or e-reader, is ahandheld device that is used primarily for read-ing e-books Figure An e-book, or digi-tal book, is an electronic version of a printedbook, readable on computers and other digitaldevices. In addition to books, users typically canpurchase and read other forms of digital mediasuch as newspapers and magazines. Most e-book readers have a touch screen andare Internet-enabled.
These devices usually aresmaller than tablet computers but larger thansmart phones. Many handheldcomputers communicate wirelessly with otherdevices or computers and also include a digitalpen or stylus for input. Some handheld computers have miniatureor specialized keyboards. Many handheldcomputers are industry-specific and servethe needs of mobile employees, such asmeter readers and parcel delivery people Figure , whose jobs require them tomove from place to place. Figure An e-book reader. How popular is text messaging?
A recent study indicates that people are using their smart phones and cell phones for voice communications andtext messaging more frequently than in previous years. Because of the increase in smart phone sales and theease with which individuals can send text messages, approximately two billion text messages are sent each day.
Introduction to Computers Chapter 1 23Some portable media players are Internet-enabled so that you can access Web sites andsend e-mail messages directly from the device. Many offer personal information managementfunctions such as a calendar and address book,and include a variety of games and other appli-cation software.
Portable media players usually include a setof earbuds, which are small speakers that restinside each ear canal. Some portable mediaplayers have a touch screen, while others havea touch-sensitive pad that you operate with athumb or finger, to navigate through digitalmedia, adjust volume, and customize settings. Digital Cameras A digital camera is a devicethat allows users to take pictures and storethe photographed images digitally, instead ofon traditional film Figure While manydigital cameras look like a traditional camera,some are built into smart phones and othermobile devices.
Although digital cameras usually have someamount of internal storage to hold images, mostusers store images on small storage media suchas memory cards. Digital cameras typically allowusers to review, and sometimes modify, imageswhile they are in the camera. Some digital cam-eras connect to or communicate wirelessly witha computer or printer, allowing users to printor view images directly from the printer. Somememory cards can connect to a network wire-lessly, so that you can transfer photos directlyfrom the memory card in the camera to theInternet without requiring a computer.
Often users prefer to download images fromthe digital camera to the computer. Or, you canremove the storage media such as a memorycard from the digital camera andinsert it in a card reader in orattached to the computer.
Figure This handheld computer is alightweight computer that enables deliverypeople to obtain and record information abouttheir deliveries.
Figure With adigital camera, users canview photographed imagesimmediately through a smallscreen on the camera to see ifthe picture is worth keeping. Portable Media Players A portable mediaplayer is a mobile device on which youcan store, organize, and play digital media Figure With most, you download the digital mediafrom a computer to the portable media playeror to media that you insert in the device.
Weighingon average between two and nine pounds,the compact size of game consoles makesthem easy to use at home, in the car, in ahotel, or any location that has an electricaloutlet.
Read InnovativeComputing to find out how the medicalfield uses the Nintendo Wii. A handheld game console is small enough tofit in one hand, making it more portable thanthe standard game console. With the handheldgame console, the controls, screen, and speakersare built into the device. Because of theirreduced size, the screens are small — threeto four inches.
Some models use cartridges tostore games; others use a memory card or aminiature optical disc. Many handheld gameconsoles can communicate wirelessly withother similar consoles for multiplayer gaming. In addition to gaming, many game consolemodels allow users to listen to music, watchmovies, keep fit, and connect to the Internet.
Wii a Welcome Medical Skill BuilderA patient awaiting laparoscopic proceduresmay be less tense knowing that the surgeonshave honed their dexterity and coordinationusing a NintendoWii. Preliminarystudies havefound that doc-tors can improvetheir fine motorcontrol by play-ing video gamesthat emphasizesubtle handmovements used in minimally invasivesurgeries. Researchers are developing Wiisurgery simulators that will allow doctorsto practice their skills at home or in breakrooms at hospitals.
The Wii game system is finding a medicalhome in other nontraditional places. Physicaltherapists urge arthritic patients to useWiihabilitation to build endurance andincrease their range of motion. Introduction to Computers Chapter 1 25ServersA server controls access to the hardware,software, and other resources on a network andprovides a centralized storage area for programs,data, and information Figure Servers cansupport from two to several thousand connectedcomputers at the same time.
In many cases, one server accesses data, infor-mation, and programs on another server. Inother cases, people use personal computers orterminals to access data, information, and pro-grams on a server. A terminal is a device with amonitor, keyboard, and memory. MainframesA mainframe is a large, expensive, powerfulcomputer that can handle hundreds or thou-sands of connected users simultaneously Figure Mainframes store tremendous amounts ofdata, instructions, and information.
Most majorcorporations use mainframes for business activi-ties. With mainframes, enterprises are able tobill millions of customers, prepare payroll forthousands of employees, and manage thousandsof items in inventory. One study reported thatmainframes process more than 83 percent oftransactions around the world. Mainframes also can act as servers in a networkenvironment.
Servers and other mainframes canaccess data and information from a mainframe. People also can access programs on the main-frame using terminals or personal computers. SupercomputersA supercomputer is the fastest, most powerfulcomputer — and the most expensive Figure The fastest supercomputers are capableof processing more than one quadrillion instruc-tions in a single second.
With weights thatexceed tons, these computers can store morethan 20, times the data and information ofan average desktop computer. Applications requiring complex, sophisticatedmathematical calculations use supercomputers. Large-scale simulations and applications in medi-cine, aerospace, automotive design, online bank-ing, weather forecasting, nuclear energy research,and petroleum exploration use a supercomputer. Figure Mainframe computerscan handle thousandsof connectedcomputers andprocess millionsof instructions persecond.
Figure A server controlsaccess to resourceson a network. Embedded computers are every-where — at home, in your car, and at work. Thefollowing list identifies a variety of everydayproducts that contain embedded computers.
These computersperform various functions, depending on therequirements of the product in which theyreside. Embedded computers in printers, forexample, monitor the amount of paper in thetray, check the ink or toner level, signal if apaper jam has occurred, and so on. Figure shows some of the many embedded computersin cars. Cars equipped with wireless communicationscapabilities, called telematics, include suchfeatures as navigation systems, remotediagnosis and alerts, and Internet access.
Drive-by-wire systems sense pressureon the gas pedal and communicateelectronically to the engine how muchand how fast to accelerate.
Introduction to Computers Chapter 1 27Elements of anInformation SystemTo be valuable, information must be accurate,organized, timely, accessible, useful, and cost-effective to produce. Generating information froma computer requires the following five elements: Figure shows how eachof the elements of an information system in anenterprise might interact.
The hardware must be reliable and capable ofhandling the expected workload. The softwaremust be developed carefully and tested thor-oughly. The data entered into the computermust be accurate. Most companies with mid-sized and largecomputers have an IT information technology department. Staff in the IT department shouldbe skilled and up-to-date on the latest technol-ogy. IT staff also should train users so that theyunderstand how to use the computer properly. Finally, all the IT applications should havereadily available documented procedures thataddress operating the computer and using itsprograms.
Step 1IT staff people develop processes procedures for recording checks data received from customers. Step 2Employees people in the accounts receivable departmentuse a program software to enter the checks data inthe computer.
Step 3The computer hardware performs calculations requiredto process the accounts receivable data and stores the resultson storage media such as a hard disk hardware. Step 4Customer statements, the information, print on a corporateprinter hardware. How the Elements of an Information System in an Enterprise Might InteractFigure This figure shows how the elements of an information system in an enterprise might interact. To illustrate the range of uses forcomputers, this section takes you on a visual andnarrative tour of five categories of users: This is usually the largest circuit-board in the computer, and every other component in the computer connects to it.
The CPU is the brain of the system. It executes all the program code from the operating system and the applications the user runs and processing of data. It sends CPU commands to direct the actions of all the other components in the computer. If the computer loses power, anything stored in RAM is lost.
The most common type of storage device, which nearly all computers have, is a hard drive. Mouse Mouse is a pointer device. The mouse allows an individual to control a pointer in a graphical user interface GUI.
Utilizing a mouse a user has the ability to perform various functions such as opening a program or file and does not require the user to memorize commands.
Digital camera A type of camera that stores the pictures or video it takes in electronic format instead of to film. Web Cam A camera connected to a computer that allows anyone connected to the Internet to view still pictures or motion video of a user.
Joystick A computer joystick allows an individual to easily navigate an object in a game such as navigating a plane in a flight simulator. Keyboard One of the main input devices used on a computer, a computer keyboard looks very similar to the keyboards of electric typewriters, with some additional keys. Microphone Sometimes abbreviated as mic, a microphone is a hardware peripheral that allows computer users to input audio into their computers.