Components of Information Technology
An information system is a group of components integrated together to collect, store, and process data. It delivers valuable information after processing the data. Organizations, business or otherwise, are dependent on an information system to control and manage their business operations. They need an information system to manage customer and supplier relationships, compete with other organizations, etc.
Business organizations use information systems to achieve their target potential customers by managing the organization’s financial accounts and human resources. Information systems have simplified many human activities, which has made a positive impact on society.
Table of Contents
These systems have increased the speed of daily activities and enhanced the efficiency of organizations. Data is a crucial part of information systems, and after being processed, this data delivers us knowledge and information. This information has become a vital economic resource for every organization.
An information system comprises many components, which are used to input, process, and output data in the form of information. The main components of an information system are computer hardware, software, data, human resources, and procedures. Hardware and software are the components of IT, which is now a vital part of operations and management in organizations.
This chapter starts by explaining the different types of hardware devices, namely input devices, output devices, and storage devices. Further, it explains software concepts, namely, operating systems, programming languages, and ready-made packages and their operating systems.
Hardware
In today’s world, every business organization, whether small or big, owns or leases computers. An organization or an individual can own one or more computers in the form of laptops, tablets, smartphones, or any other portable device.
Large organizations have distributed computer systems located in remote data centers. These organizations also use mobile devices, which are integrated into the organizational information system.
Together, all the peripheral equipment, such as storage discs, input-output devices, and telecommunication devices, constitute the hardware of an information system. In the last few years, the cost of hardware has rapidly decreased, whereas the cost of processing speed and storage capacity has increased. However, the power consumption of hardware is still a major concern being addressed by business organizations.
Hardware can be described as the collection of physical components of a computer or the parts of a computer that can be physically touched. Most hardware contains physical parts such as circuit boards, ICs (Integrated Circuits), and other electronic parts.
A computer monitor is an example of hardware, which displays information on a screen. A computer cannot exist without hardware. Also, software applications cannot run without hardware.
Computer hardware consists of four types of devices, as shown in Figure:
Let us discuss these types of hardware in detail.
Input Devices
Any hardware device that is used to enter data to a computer is known as an input device. Input devices allow a user to perform numerous tasks interactively with the computer. Without input devices, a user is not able to interact with a computer.
Some most common input devices are discussed as follows:
Keyboards
The most common input device used with computers is a keyboard. It is similar in appearance to the traditional typewriter, but it has some extra keys, which have their own purpose. Keyboards allow users to input letters, numbers, and other symbols into the computer, which enables users to write documents such as e-mails, business reports, and business documents.
Figure shows the layout of a typical keyboard:
| Keys | Description |
|---|---|
| Windows | This is commonly used in combination with other keys. For example, Windows key + E is used to open Windows explorer |
| F1 – F12 | Function keys have different users based on the operating systems and the application. For example, in a Windows operating system, F1 is used to open the Help window. |
| Tab | The Tab key is used to give indention between lines and switch between controls such as menu bars and text boxes. |
| Caps lock | This is used to type capital letters |
| Shift | This is used to type a single capital character. It is also a modifier key, which is used in combination with other keys. |
| Ctrl | The Ctrl (control) key is mainly used to perform various keyboard shortcuts such as ctrl + c for copying data. |
| Alt | The Alt (alternate) key is a modifier key that is used in combination with other keys. For example, pressing Alt + F4 is used to close the currently open program. |
| Back Space | This is used to delete text backward |
| Delete | This is used to delete text, files, and other objects from the computer’s hard drive. |
| Enter | This is used to place the cursor on the next line and to execute a command |
| Space bar | This is used to enter space between text. |
| Esc | This is used to escape a program. |
| PrtScrn | This is used to print the currently open document. |
| Scroll lock | This is used to lock the scroll bar and temporarily stop the scrolling of text. |
| Pause | This is used to pause the actions of the program being run or the scrolling of text. |
| Break | This is used to break the pause or other halt state of the computer |
| Insert | This is used to change the cursor type. |
| Home | This is used to return the cursor to the beginning of a line or a document |
| Page up | This is used to move one page up. |
| Page down | This is used to move one page down. |
| Arrows | This is used to move the cursor in different directions such as up, down, left and right. |
| Num Lock | This is used to enable and disable the numeric keypad |
| Indicator | This is used to notify the user about the status of the different lock keys. |
| Menu | This is used to open the context menu of the program which is clicked. |
| Alphabetic Keys | This is used to enter alphabet. |
| Numeric keys | This is used to enter numbers. |
Through many years, the keyboard has evolved with new technologies. Its design has changed many times in the past several years, but the basic layout of the keyboard is still the same. However, variations of the common keyboard are now available.
Following are some different types of keyboards:
Standard Keyboard
A standard keyboard has 105 keys on average, however, some still older versions of keyboards, with the number of keys ranging from 95 – 103, also exist. Standard keyboards are the most basic keyboards, but they still have variations in their key placement.
QWERTY keyboards are the most commonly used keyboards. They are called QWERTY keyboards, because the six alphabets, Q, W, E, R, T, and Y, are in the first row. Similarly, AZERTY, QWERTZ, and Dvorak keyboards are other variations of a standard keyboard.
Figure shows a QWERTY keyboard:
Ergonomic Keyboards
Ergonomics is the study of methods that reduces stress on muscles to avoid a strain injury. It emphasizes correct positions and techniques while working so that the work is done with the least possible strain on any muscle. An ergonomic keyboard is designed with these concerns in mind.
The design of an ergonomic keyboard is based on ergonomics. It is slightly broader than and different from standard keyboards. These keyboards are used by people who spend long hours working on keyboards to avoid stress in their wrist muscles.
The figure shows an ergonomic keyboard:
Wireless Keyboards
Wireless keyboards do not need a wire to connect to the computer. Such a keyboard is more comfortable to use because you can work on it at a certain distance from the monitor. Wireless keyboards use different technologies, such as Bluetooth, infrared, and radio frequency, to connect to the computer.
These keyboards run on batteries and have a transceiver, which connects to the computer and establishes a connection between the computer and the keyboard.
The figure shows a wireless keyboard and a transceiver:
Mouse
A mouse is an input device that is used to point to an object on the screen. It performs various tasks by its two-click buttons known as the left-click and the right-click buttons. The mouse sends information to the computer when the user presses the click buttons and the computer performs the task after processing the command.
The user can also consider the mouse as an alternative to the various MS-DOS commands because, with the help of the mouse, the user does not have to remember MS-DOS commands such as cd, mkdir, and dir.
Figure shows a mouse and its parts:
As new technologies arrive, new types of the mouse have entered the market. Some different types of the mouse are as follows:
Mechanical Mouse
A mechanical mouse has a ball inside it, which is made of rubber or metal. The movement of the ball determines the position of the cursor on the screen.
Figure shows a mechanical mouse:
Optical Mouse
Unlike a mechanical mouse, an optical mouse does not contain any ball inside it. It uses optical sensors or lasers, which emit light to detect the mouse’s movement. It is costlier than the mechanical mouse.
Figure shows an optical mouse:
Wireless Mouse
A wireless mouse has no wire attached to it. It does not require a wire or a cable to work. Instead, it uses wireless technologies such as Bluetooth and infrared. It transmits data with the help of radio waves or infrared light waves. A receiver is connected to the computer using a USB port, and the mouse has a transmitter built in it. This mouse provides the freedom of working on a computer from a distance.
Figure shows a wireless mouse and a transceiver:
Scanners
Organizations often encounter situations where they need to convert a physical document into an electronic document to read or edit it. In such situations, they can use scanners.
A scanner is used to scan a text document or an image and convert it into a digital file. A scanner allows the computer to read, display, and edit the scanned document on the screen. Most scanners have a flat scanning surface, hence, they are also called flatbed devices.
There are some other popular types of scanners such as:
- Sheetfed Scanner: A sheetfed scanner scans the document fed into it.
- Handheld Scanner: A handheld scanner is held and dragged over a document to scan it. It is commonly used in general stores to scan product information.
Figure shows flatbed and handheld scanners:
Digital Camera
A digital camera is a camera that stores images digitally instead of capturing them on film. It is stored in electronic format so you can store and edit images on your computer. There are various photo editing computer applications that you can use to edit your images. Images captured with digital cameras have a limited resolution due to the limited amount of memory in the camera.
Figure shows a digital camera:
Joystick
Joystick is an input device that is used to control objects in computer games. For example, gaming parlors use these devices for arcade games. With the help of joystick, you can move an object in a game such as driving a car in a driving simulator game.
Figure shows a joystick:
Touch Screen
A touch screen can be described as a flat surface with a sensitive panel. This touch-sensitive panel takes the touch of a finger as input. Using the touch screen you can interact with devices without a mouse of the keyboard for input.
It is used in the public environment where people only need general information, for example, ATM machines. However, with the rapid growth and demand of this technology touch screens are mainly used in small devices such as smartphones and tablets.
Figure shows a touchscreen mobile phone:
Light Pen
A light pen is a pointing device and used to give input to the computer. It is shaped like a pen and connected to the computer. There is a light-sensitive element in the light pen that detects light from the screen when placed against it. This allows the computer to identify the location of the pen on the screen.
Figure shows a light pen:
Processing Devices
Organizations analyze and calculate huge amounts of data with the help of a computer. A computer performs various calculations through its processing devices.
In a computer, processing devices control the storage and retrieval of information. The CPU (Central Processing Unit) is a processing device found in computers. The information is processed through the CPU, which performs various operations on data such as calculation and comparison.
Every computer contains processing devices. Users cannot perform operations on data without processing devices. Other than the CPU, devices, such as graphics cards, computer memory, network card, and others, are also processing devices.
Figure shows processing devices:
Storage Devices
Whenever a user creates a new document, such as a business report or an analytical report, the user needs to save it, so that it can be reused. Saving data is important in an organization because any loss of data can lead to problems or loss.
In a computer, a user saves data in storage devices. A storage device is a hardware device that holds user data.
There are two types of storage devices used in computers: primary storage devices, such as a computer Random Access Memory (RAM), and secondary storage devices such as a computer hard drive. Without a storage device, a computer cannot save any information. There are different types of storage devices.
Figure shows some important storage devices:
These storage devices are discussed as follows:
Random Access Memory
RAM is the primary memory of a computer system. It is a storage device that allows information to be stored and retrieved quickly from a random location in the memory. For example, when we copy text from a document, the text is stored for a short amount of time in the RAM.
Data is retrieved randomly in RAM and not sequentially, thus, the computer accesses data faster as compared to data retrieval from a hard disc. RAM is a volatile memory because it needs electric power to keep the data available.
All the data stored in memory will be lost if power is lost. Figure shows RAM:
Read Only Memory
Read Only Memory (ROM) is a built-in memory in computer systems, which can hold data and read that data from the chip, but it cannot write data. ROM is a non-volatile memory, unlike RAM, which means it maintains and stores information in itself regardless of the presence of electric power.
For example, system settings are stored in the ROM, which are not lost even when power is switched off.
Figure shows ROM:
Compact Discs
Compact Discs (CDs) are storage devices and are read by a laser in a CD-ROM drive. A CD-ROM drive is a CD player inside a computer system. CDs are round in shape and can store up to 700 MBs (Mega Bytes) of data.
They can store any type of data. For example, an audio file, video file, or any other digital file. A CD is often used in organizations to store business presentations.
Figure shows a CD:
Hard Drive
A Hard Disc Drive (HDD) or a Hard Drive (HD) is a secondary storage device in a computer system. It is also the main storage device that stores data permanently in the computer.
The HD contains rapidly rotating discs called platters inside air-sealed casings, which are coated with magnetic material. It holds its data even when there is no power.
HDs enables users to maintain and reserve data over a long period of time. For example, organizations can store business reports on a hard disc permanently.
Figure shows an HDD:
Output Devices
A peripheral device that receives or displays output from a computer is called an output device. When a user inputs data into a computer, the computer processes the data and shows the result on the computer monitor. A monitor is the most common example of an output device.
Figure shows some examples of important output devices:
The output devices are discussed further:
Monitor
A computer monitor, also known as a Visual Display Unit (VDU), is an output device that displays the information from the CPU on the screen. It works as an interface between the user and the CPU. A monitor is connected to a video adapter through a cable.
The CPU instructs the video adapter regarding the information to be displayed on the screen. Then the video adapter converts the instructions into corresponding signals and sends them to the monitor. The monitor comprises circuitry that generates the content to be displayed on the screen.
Figure shows a computer monitor:
Printer
An organization deals with a large number of documents on a daily basis. These documents are on the computer system and are often required to be printed on pages. Printers are used to print such documents.
A printer is an output device, which generates the hard copy of data residing in the computer system. In an organization, printers are used on a wide scale to print text, images, business reports and other important documents. There are many types of printers such as dot matrix printers and laser printers.
Figure shows a printer:
Projector
A projector is an output device that can project the computer screen on a large flat surface. Projectors are commonly used in business meetings and presentations to ensure that everyone can see the information.
Figure shows a projector:
Software Concepts
Software is a well-organized collection of instructions and code that is written by programmers to achieve a predefined objective. The software enables users to interact with a computer and perform various operations. Software is an essential part of a computer system.
Without software, computers are useless. For example, without the help of a Web browser, users cannot access the Internet. Also, without an operating system, which is also a type of software, the browser cannot run on a computer. There are two types of software, discussed as follows:
- System Software: System software is designed to control and operate other computer programs. The operating system is an example of system software because it manages other software programs. Other software applications, which are installed with an operating system, also exist.
These applications are sometimes also called system software because they are a part of the operating system. This kind of system software can be necessary for other applications to function properly.
All system software is not used by users directly, some system software runs in the background. For example, when a user installs a windows operating system, Internet Explorer (IE) is automatically installed with it.
Although it is not necessary for a user to use IE because other Web browsers are available for free. Still, numerous applications rely on the components of IE to function properly.
- Application Software: Application software is a software program that is designed to perform specific tasks. Some examples of application software are Web browsers, word processors, spreadsheets, and other utility applications. Consider the example of a word processor.
Organizations always need to create various reports and legal documents for different purposes. They use the word processor program to create such documents because it provides various utilities such as different fonts, colors, and layouts.
System software run in the background and enable other applications to run. This system software consists of programs such as an assembler, compiler, and file management system. Application software run on top of this system software.
System software are installed automatically when a user installs an operating system, whereas in case of application software, the user can decide which application to install.
Operating Systems
An operating system is a software program that allows the computer hardware to communicate with the computer software. It also controls and manages application software in a computer system.
A computer is useless without an operating system. The most commonly used operating systems used in an organization are Microsoft Windows XP/7/8, Linux Ubuntu, and Macintosh OSX.
When computers were first introduced, users interacted with computers through commands. Memorizing all the difficult commands was not easy, because sometimes users needed to perform a series of commands.
Today, every computer uses a GUI (Graphical User Interface) based operating system, which consists of buttons, menu bars, textbox, etc., and is much simpler to operate.
Figure provides an overview of the working of an operating system:
Programming Languages
A programming language is used to create computer programs such as software applications. A programming language contains predefined instructions, which are used to create computer programs.
Computer programmers write these instructions to command the program to perform its tasks. After writing the complete program, it is compiled using a compiler.
A compiler turns a programming language into a machine language, which a computer understands. Then the compiler generates an executable file, which the user can run on a computer.
Using a programming language, programmers can develop different kinds of software applications such as GUI applications and Web applications. Following are some popular programming languages, which are used to create applications:
- C
- C++
- Java
Ready-made Packages and Their Operating Systems
Ready-made packages are ready to use. The user only needs to install these programs and they can start using them. Ready-made packages comprise computer programs, user guides, and other documentation sets.
They provide inexpensive and quick solutions to numerous computer applications. A wide range of ready-made packages is available in the market. Some examples of such packages are Microsoft Office, Libre Office, Kingsoft Office, etc.
Such applications are used on a large scale in a business organization. These applications should be compatible with the user’s operating systems to function properly. The user should always check the system requirements of the application package before purchasing it.
There are many software packages that are built for a specific operating system. For example, the Microsoft Office package only runs on Windows operating systems.
Let us discuss some important applications that organizations need in ready-made software packages:
- Word Processor: Word processor is an application that allows users to perform almost all types of operations on text. It allows users to create, edit, and format documents. It also allows users to add pictures, graphs, and tables in documents.
One of the most popular word processors is Microsoft Word, which comes in the Microsoft Office package and runs on the Windows operating system. - Spreadsheet: A spreadsheet is a document that consists of rows and columns for entering data. This data is recorded in spreadsheets to perform various calculations.
In an organization, a spreadsheet is mostly used for accounting purposes such as creating balance sheets. Microsoft Excel is an example of a spreadsheet program. - Relational Database Management System (RDBMS): An RDBMS is used to store data in the format of rows and columns. This combination of rows and columns forms a table. These tables can have relations with other tables.
For instance, a table that stores product data can be related to a customer table. Microsoft Access is an example of an RDBMS, which is found in Microsoft Office.
