INTRODUCTION TO COMPUTERS QUESTION BANK 2013

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1 Chapter 1: HARDWARE 1. Define I. Data A Data can be defined as unprocessed information. II. Information An Information can be defined as a processed data. Data processed Information processed Knowledge 2. Mention several i/p devices. I. Keyboard most common input device used to input text, numbers & instructions into the computer. Most of the use QWERTY layout. II. Numeric Keypad Telephones and ATMs [Automatic Teller Machines] use numeric keypad to enter data allowing entry of numbers only. III. Mouse is actually an example of pointing device usually having two buttons where left button is used to select something by double clicking it & the right button brings up drop-down menus. IV. Touchpad used in many laptop computers as a pointing device usually controlled by the user moving their finger or gently tapping it to simulate the left/right button of the mouse. V. Tracker ball similar to a mouse except that the ball is on the top of the device & the user controls the pointer on the screen by rotating the ball with the hand. VI. Remote control used to control the operation of other devices remotely by using infra red signals. Most home entertainment devices such as television, satellite systems, DVD player, hifi systems have remote controls. VII. Joystick has similar functions to mice and tracker balls. By gripping this stick, a pointer on the screen can be controlled & buttons are used for selections. Often they have another button on the top of the stick that is used for gaming purposes. VIII. Touch screen With the system of touch screen, the user can choose an option by simply touching the button/icon on the screen. E.g.: PDAs [Personal Digital Assistants], mobile phones, etc.. IX. Smart Card Reader used to read information stored on a chip (Smart Card). E.g.: ID cards, Loyalty cards, etc. X. Scanner used to enter information on hard copy into a computer. The most common scanner is the flat-bed which is made up of a glass panel and lid. XI. Barcode reader used to read information in the form of a bar code. It is used as a safety function in many companies to ensure that electrical equipment is checked on a regular basis. XII. OMR [Optical Mark Recognition] is a system which can read marks written in pen or pencil. It is used to read questionnaires, multiple choice examination papers & other forms where responses are registered in the form of lines or shaded areas. XIII. OCR [Optical Character Recognition] is the name given to software that takes scanned text and converts it into a computer readable form. It is used while scanning documents so that they can be modified using a word processor or desktop publisher package. XIV. MICR [Magnetic Ink Character Recognition] is a system which can read characters printed in a special ink [containing iron particles]. Only characters written in a standard font can be read. It is primarily used to process cheques in banking operations. 1

2 XV. XVI. XVII. XVIII. XIX. XX. Digital Camera is rapidly replacing traditional, film-based cameras. Once photographs are stored in memory, they are easily transferred to a computer using a Universal Serial Bus (USB) connection. Webcam is similar to digital video camera, however it is connected directly to the computer and do not have a memory. Many computers have webcams built into the top of their monitors as standard equipment used to enable video-conferencing. Microphone can be connected directly to a computer. Sounds can be inputted and manipulated. It is used in voice recognition software which can have a number of purposes such as conversion of speech into text that can be used in word processor & for recognition commands. Sensor is a device which inputs data to a computer where the data is a measurement of some physical quantity which is continuously changing, such as temperature, light, moisture, etc.. Graphic tablet used with a stylus to produce freehand drawings as in Computer Aided Design (CAD) work. Light pen contain sensors that sends signals to a computer whenever light changes are detected. They are also used for drawing onscreen. 3. Mention several o/p devices. I. CRT [Cathode Ray Tube] Monitor least expensive type of monitors, although they are becoming increasingly rare as TFT monitors are now taking over. It uses an electron gun to fire against a phosphor screen, which creates a picture that is made up of tiny dots. II. TFT [Thin-Film Transistor] Monitor The screen us made up of thousands of tiny pixels, which are made up of transistors controlled by a microprocessor. III. Laser Printer produces very high-quality hard copy output. The print rate per page is very high if a number of pages are being printed. IV. Inkjet Printer produces good quality hard copies. Although the quality is not as quite as good as that from the laser printer, it is far better than that from dot matrix printers. V. Dot-matrix Printer is a type of impact printer, where a print-head (made up of matrix of pins) presses against an inked ribbon. It tends to be slow, noisy and the output is not of a good quality. VI. Plotter produces hard copies, but operates in a different way to printers. It is not limited to normal printer paper size but is capable of producing highly accurate, very large drawing and posters. VII. Speaker can be connected directly to a computer or is built into the monitor or casing Digital data from the computer is converted into analogue, using a Digital to Analogue Converter (DAC). VIII. Multimedia Projector receive signals that can either be analogue or digital, although the most modern projectors only work with digital inputs. The signal source is usually from a computer, television or DVD player. IX. Terminal - is used for entering data into, and displaying data from, a computer or a computing system. 4. Mention several Storage devices. 2

3 I. Magnetic i. Fixed hard disk has read/write heads that allows data to be written to or read from the disk surface. ii. Portable hard disk usually connected to the computer via a Universal Serial Bus (USB) port and can be disconnected and used on different computers. iii. Floppy disk drive used on some computers consisting thin disk of plastic which is housed in a plastic case with a window where the disk can be assessed. iv. Magnetic tape is a very thin strip of plastic coated in a magnetic layer read and written by a read/write head. II. Optical i. CD-ROM & DVD-ROM are Read Only Memory (ROM) which means they cannot be written over and can only be read. ii. CD-R & DVD-R are the disk which are recordable only once and then it becomes a CR- ROM or DVD-ROM. The letter R here means the disk is recordable only once. iii. CD-RW & DVD-RW The RW means these disks are re-writable media and can be written over several times. Unlike CD-R/DVD-R they do not become ROMs. iv. DVD-RAM is a recent addition to the optical media group. Unlike the CD and DVD formats, DVD-RAMs have several discrete concentric tracks giving them the advantage that writing and reading can occur at the same time. v. Blu-ray disk has the largest capacity of all the optical media available and go up to 100 GB at present. III. Solid State i. Memory sticks / Pen drives it can store several GBs of data and use the solid state technology usually connected through the USB port and power to operate it is drawn from the host computer. ii. Flash memory card is a form of Electrically Erasable Programmable Read Only Memory [EEPROM]. It is used to store photos in digital cameras. Mobile phones use them as memory cards. 5. Describe in brief the Generation of Computers. 3 First Generation ( ) : Vacuum Tubes The first computers used vacuum tubes for circuitry and magnetic drums for memory, and were often enormous, taking up entire rooms. They were very expensive to operate and in addition to using a great deal of electricity, generated a lot of heat, which was often the cause of malfunctions. First generation computers relied on machine language, the lowest-level programming language understood by computers, to perform operations, and they could only solve one problem at a time. Input was based on punched cards and paper tape, and output was displayed on printouts. The UNIVAC and ENIAC computers are examples of first-generation computing devices. The UNIVAC

4 was the first commercial computer delivered to a business client, the U.S. Census Bureau in Second Generation ( ) : Transistors Transistors replaced vacuum tubes and ushered in the second generation of computers. The transistor was invented in 1947 but did not see widespread use in computers until the late 1950s. The transistor was far superior to the vacuum tube, allowing computers to become smaller, faster, cheaper, more energy-efficient and more reliable than their first-generation predecessors. Though the transistor still generated a great deal of heat that subjected the computer to damage, it was a vast improvement over the vacuum tube. Second-generation computers still relied on punched cards for input and printouts for output. Second-generation computers moved from cryptic binary machine language to symbolic, or assembly, languages, which allowed programmers to specify instructions in words. High-level programming languages were also being developed at this time, such as early versions of COBOL and FORTRAN. These were also the first computers that stored their instructions in their memory, which moved from a magnetic drum to magnetic core technology. The first computers of this generation were developed for the atomic energy industry. Third Generation ( ) : Integrated Circuits The development of the integrated circuit was the hallmark of the third generation of computers. Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers. Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with an operating system, which allowed the device to run many different applications at one time with a central program that monitored the memory. Computers for the first time became accessible to a mass audience because they were smaller and cheaper than their predecessors. Fourth Generation (1971-Present) : Microprocessors The microprocessor brought the fourth generation of computers. Unlike the first generation computers which filled an entire room could now fit in the palm of the hand. The Intel 4004 chip, developed in 1971, located all the components of the computer from the central processing unit and memory to input/output controls on a single chip. In 1981 IBM introduced its first computer for the home user, and in 1984 Apple introduced the Macintosh. Microprocessors also moved out of the realm of desktop computers and into many areas of life as more and more everyday products began to use microprocessors. As these small computers became more powerful, they could be linked together to form networks, which eventually led to the development of the Internet. Fourth generation computers also saw the development of GUIs, the mouse and handheld devices. Fifth Generation (Present and Beyond) : Artificial Intelligence Fifth generation computing devices, based on artificial intelligence, are still in development, though there are some applications, such as voice recognition, that are being used today. The use of parallel processing and superconductors is helping to make artificial intelligence a reality. Quantum

5 computation and molecular and nanotechnology will radically change the face of computers in years to come. The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization. 6. Describe in brief several types of computers. I. Desktop - most common type of personal computer that is designed to sit on or under a desk or table commonly used in schools, offices and home. II. Workstation a specialized, single-user computer that typically has more power and features than a standard desktop PC popular among scientists, engineers and animators who need a system with greater than average speed and the power to perform sophisticated tasks. III. Laptops Notebook computers as their name implies, approximate the shape of an 8.5 by 11 inch notebook and easily fit inside a briefcase. Several notebook systems are designed to be plugged into a docking station, which may include a large monitor, a full size keyboard and mouse or other devices. IV. Tablet PCs newest development in portable, full featured computers offering all the functionality of a notebook PC & are lighter and can accept input from a special pen called a stylus or digital pen that is used to tap or write directly on the screen. V. PDA [Personal Digital Assistant] handheld personal computers small enough to fit in your hand. Many PDAs let the user access the Internet through a wireless connection. VI. Smart phones Some cellular phones double as miniature PCs because they offer advanced features not typically found in cellular phone. So they are called as Smart Phones. The advanced features include Web and access, special software such as personal organizers or special hardware such as digital cameras or music players. Some models even break in half to reveal a miniature keyboard. VII. VIII. Network Server In most organizations, individual users have their own desktop computers which are connected to one or more centralized computers called network servers. A network server is usually a powerful computer with special software and equipment that enable it to function as the primary computer in the network. Mainframe used in large organizations such as insurance companies and banks where many people frequently need to use the same data. In a traditional mainframe environment, each user accesses the mainframe s resources through a device called a terminal. IX. Minicomputers are small sized computers as compared to other computers of the day. The capabilities of a minicomputer are often called as midrange computers. X. Supercomputer is the most powerful computer made and physically they are some of the largest. They can process huge amounts of data and the fastest supercomputers can perform more than ONE TRILLION calculations per second. 5 Chapter 2: Software 7. What is software? How is it classified? Computer software, or just software, is any set of machine-readable instructions (most often in the form of a computer program) that directs a computer's processor to perform specific

6 operations. Hardware and software require each other and neither has any value without the other. Software is broadly classified in two categories: System software and Application Software. Operating System System Assemblers Software Debuggers Word Processor Application Spreadsheet Communication Software System software controls the operations of the computer and computer equipment. It can be further categorized in 3 types: System Management Software (O.S., DBMS, etc.), System development Software (Assemblers, translators, etc.) and System software utilities (Debuggers, etc.). 8. Discuss different types of Operating System. Operating Systems are generally classified in 4 types based on the types of computers they control and the sort of applications they support. 1) Real-time Operating Systems [RTOS] The main objective is their quick and predictable response to events. They either have an event-driven or a time-sharing design. An event-driven system switches between tasks based on their priorities while time-sharing operating systems switch tasks based on clock interrupts. 2) Single user, single task It is designed to manage the computer so that one user can effectively do one thing at a time. The Palm OS for handheld computers is an example of a modern single-user, single task operating system. 3) Single-user, multi-task This is widely used on desktop and laptop computers today. Several OS let a single user have several programs in operation at the same time. 4) Multi-user This allows many different users to take advantage of the computer s resources simultaneously. Mainframe computers are example of multi-user operating system. 9. Discuss different Operating Systems in brief. 1) DOS DOS (Disk Operating System) offers many advantages to the user by being stable and rarely tolerates crashes. It is a CUI [Character User Interface] based single user operating system developed by Microsoft and was used in IBM computers. While the system is still used, DOS has 6

7 become more difficult to manage as support is limited. DOS performs operations quickly as compared with Windows Operating System. 2) Linux Linux is an alternate to UNIX. It is a GUI [Graphical User Interface] and considered as most secure platform allowing users and developers to access the source code for free. As it requires less hardware, it is capable of performing exceptionally even on a smaller hard disk. It is created by Linus Torvalds at the University of Helsinki in the year ) Mac OS X This is Apple s trademark operating system software for their line of Macintosh computers. The system was based in part on UNIX [Darwin] and mimics its format with the administrative controls. Mac OS X software requires a low level of maintenance with fewer occurrences of computers worms, viruses and spyware. Mac OS X provides a new user interface called AQUA which gives high visual appearance to the user with transparent buttons, scrollbars, etc. 4) Windows The Microsoft Windows Operating system is the most popular choice and currently has a strong hold on the market. This platform has made significant advancements from version 1.0 all the way to the new Windows 8.1 system. It is highly compatible, feature-rich and has a much larger selection of software applications. Windows has been associated with the term insecure as a number of security vulnerabilities have made it the most targeted system. 7

8 Types of Networks INTRODUCTION TO COMPUTERS QUESTION BANK What is a software license? What are its types? [Refer your handwritten notes for answer] 11. What are the different types of application software? [Refer your handwritten notes for answer] Chapter 3: Networking Basics 12. What is a Network? What are its types? A Network is defined as group of computers connected together to share the resources (hardware and software) with two principle benefits: the ability to communicate and the ability to share. Basic LAN WAN Local Area Network Wide Area Network MAN Metropolitan Area Network CAN Campus Area Network Advanced PAN SAN Personal Area Network Storage Area Network HAN Home Area Network WLAN Wireless LAN LAN [Local Area Network]: supplies networking capability to a group of computers in close proximity to each other such as in an office building, a school or a room. It is useful for sharing resources like files, printers, games or other applications. WAN [Wide Area Network]: spans a large geographical area such as a state, province o country. The world s most popular WAN is the Internet. MAN [Metropolitan Area Network]: spans a physical area larger than a LAN but smaller than a WAN, such as a city. CAN [Campus Area Network]: spans multiple LANs but smaller than a MAN, such as on a university or college campus. PAN [Personal Area Network]: set up for personal/non-commercial usage. SAN [Storage Area Network]: connects servers to data storage devices. HAN [Home Area Network]: set up at home to connect multiple devices. WLAN [Wireless LAN]: a LAN based on Wi-Fi or wireless network technology. 13. What is meant by network topology? What are its types? Network Topology refers to the arrangement or physical layout of computers, cables and other components on the network. 8

9 Network Topologies Bus Ring Star Mesh Hybrid Refer your handwritten notes for details of every topology. Mention details in your answer. 14. What is a network media? What are its types? In Data Communication, network media plays a significant role, it decides upon the rate at which the transmission can take place with least amount of error or no error. There are two types of network media: Wired media (guided media) and Wireless media (unguided media). Refer your handwritten notes for details of every media. Mention details in your answer. Chapter 4: Data Communication 15. What is Data Communication? What are its components? [Refer your handwritten notes for answer] 16. Write a note on modem. [Refer your handwritten notes for answer] 17. Write a note on Wireless [Refer your handwritten notes for answer] Chapter 5: Internet 18. What is an Internet? What are the types of Internet Connection? An internet is defined as network of networks. It is simply a series of computers, linked to one another around the world, communicating almost instantaneously with one another. There are two types of internet connection, they are as follows: Dialup DSL Occupy a phone line Connection speed: < 56kbps Have to dial an access number to connect to the internet Connected using a computer modem Unique IP address for each connection Low monthly fee Easy setup, no setup fee Available to everyone with phone connection Phone line is not affected by internet connection 256 kbps to 20 MBPS Always on Connected through a DSL modem Static IP address Higher monthly fee Self installation is usually free. A setup fee is needed if installed by a technician. Not every phone is equipped for DSL service. 9

10 19. What are the various services offered on net? a. WWW (World Wide Web): is technically known as w3c (world wide web consortium) or more commonly as the web consists of internet servers connected through hypertext. It is basically a a community that collects of information in various types. b. technically known as electronic-mail, is a method of exchanging digital messages, designed primarily for human use. These systems are based on a store-and-forward model in which computer server accepts, forwards, delivers and stores messages on behalf of users, who only - need to connect to the infrastructure. E.g. gmail.com, yahoo.com, etc. c. FTP (File Transfer Protocol): is a standard internet protocol for transmitting files between computers on the internet. FTP allows a user to download programs and audios/videos from the Internet server to his computer. d. Chat Instant Messenger (IM): is the exchange of text messages through a software application in real-time. For chatting to work, both users must be online at the same time and the intended recipient must be willing to accept instant messages, as it is possible to configure the IM client to reject chat sessions. E.g. whatsapp, viber, etc. e. P2P (Peer-to-peer): p2p computing or networking is a distributed architecture that partitions tasks or workloads between peers (individual computer) as in mesh topology. Peers upload files to other peers and download files from them. Thus, every client is a potential server (and vice versa). f. Blogs: a blog (a contraction of the term weblog) is a simple website for a normal user. For a technical person, a blog is an online journal which is to be updated on a regular basis. The difference between a website and a blog is a website charges you an annual fee whereas a blog can be designed for free. E.g. littlevision.wordpress.com 10