Computer System

 

1. Choose the correct option:

a. GIGI refers to the errors due to .......
i. incorrect data ✔
ii. faulty hardware
iv. All of the above
iii. Program

b. ................ was the main electronic component used in third generation computer.
i. Transistor
ii. Integrated circuit ✔
iii. Vacuum tube
iv. VLSI

c. An analog computer can process ..............
i. temperature
ii. pressure
iii. speed
iv. All of the above ✔

d. In how many generations a computer can be classified?
i. 3
ii. 4
iii. 5 ✔
iv. 6

e. .......... programming language was/were used in first generation computers.
i. Machine language ✔
ii. Assembly language
iii. Both of above
iv. None of above

f. The speed in a supercomputer is measured in ...........
i. Floating point operations per second ✔
ii. Million instructions per second 
iii. Kilobits per second
iv. Gigabits per second

g.  ............. is an input device used on a computer.
i. Microprocessor
ii. Speaker
iii. Touchpad ✔
iv. printer

h. The part of CPU that performs all the processing tasks is known as ..............
i. ROM
ii. RAM
iii. Control Unit
iv. Arithmetic and Logic Unit ✔

i. The CPU performs execution of an instruction in  ..................
i. 3
ii. 4 ✔
iii. 5
iv. 6

j. Which of the following memory is non-volatile memory?
i. Hard disk drive
ii. Optical disk
iii. Pen drive
iv. All of the above ✔

k. The program stored in ROM is called ........
i. flatware
ii. freeware
iii. formware 
iv. firmware ✔

l. The cache memory is used in a computer to .........
i. store frequently used files
ii. store data and program which are most frequently used by CPU ✔
iii. store the result of processing temporarily
iv. store data and program that a user uses frequently

m. A light sensitive device that converts images or printed document into digital form is ............
i. Plotter
ii. OMR
iii. Scanner ✔
iv. Light Pen

n. A USB refers to ...........
i. storage device
ii. processor
iii. a port type ✔
iv. a serial bus standard

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2. Short answer questions:

a. Define a computer. Why is computer known as a versatile and diligent device? Explain.

Ans: A computer is an electronic programmable device that accepts data and instructions, process them and produces information as an output.

A computer is called a versatile device because it has the capability of doing various kinds of tasks. In the same way, a computer can perform tasks repeatedly without loosing speed and accuracy for a long time. So, it is called dilligent device.

b. What are the application areas of computers? Explain in brief.

Ans: A computer can perform different tasks efficiently. So it is used in almost all the fields. Some of the application area of computers are given below:

• Education
• Office
• Banking
• Industry
• Business
• Entertainment.
• Communication
• Health
• Transportation 
• E-Governance

c. Why was the size of the computer reduced in the third generation of computers?

Ans: The size of the computer was reduced in the third generation of Computers because in third generation of Computer Integrated Circuit (IC) was used insted of transistors.

d. Explain the technology used in different generations of computers.

Ans: There are five generations of Computer and in each generation Computers are more advanced and reliable than previous generation because different technologies were used in new generations. All the technology used in different generation of computer are as follows: 
i. First generation Computers = Vaccum Tube
ii. Second generation Computers = Transistor
iii. Third generation Computers =  Integrated Circuit
iv. Fourth generation Computers = LSI and VLSI
v. Fifth generation Computers = Biochips

e. Differentiate between second and third generation computer.

Ans: The differences between second and third generation computers are as follows:

2nd Generation Computers	3rd Generation Computers
Transistors were used as the main component.	Integrated Circuit (IC) were used as the main component.
Operating speed was measured in microsecond.	Operating speed was measured in nanosecond.
It was used between 1959 to 1964 AD.	It was used between. 1965 to 1974 AD.
Assembly language was used in 2nd generation of computers.	High level language was used in 3rd generation of computers.

 

f. What are the different generations of computers? Compare the third generation fourth generation of computers.

Ans: The different generations of computers are as follows:

• First generation Computer
• Second generation Computer
• Third generation Computer
• Fourth generation Computer
• Fifth generation Computer

The differences between third generation and fourth generation computers are as follows:

3rd Generation Computers	4th Generation Computers
Integrated Circuit (IC) were used as the main component.	Microprocessor were used as the main component.
Operating speed was measured in nanosecond.	Operating speed was measured in picosecond.
It was used between. 1965 to 1974 AD.	It was used between. 1975 and onwards.
High level language was used in 3rd generation of computers.	Standard High level language was used in 4th generation of computers.

 

 

g. Differentiate between analog and digital computers. 

Ans: The differences between analog and digital computers are as follows:

Analog Computer	Digital Computer
Analog computer works on the  measurement of continuous physical quantities.	Digital Computers work on discrete data (non- continuous).
An analog computer works with analog signals.	A digital computer works with digital signals.
They are slower.	They are faster.
They not versatile and are dilligence.	They are versatile and diffigence.

 

h. Differentiate between Mini and Mainframe computers.

Ans: The differences between Mini and Mainframe computers are as follows:

Mini Computer	Mainframe Computer
It was introduced in 1960.	It was introduced in 1975.
It generally consists of two or more processors.	It generally consists of multiple processors.
It can serve two to thousands connected users at a time.	It can serve hundreds to thousands connected users at a time.
It has lower memory capacity.	It has higher memory capacity.

i. What is a super computer? Explain its application in a real life situation.

Ans: Super Computer are the most powerful task specific computers which are used by large organisations for scientific and engineering applications where large databases are processed. Some applications of super computer in a real life situation are as follows:

• They are used for weather forecasting.
• They are used for studying earthquake.
• They are used for designing automobiles.

j. What is mobile computing? Explain the importance of mobile computing communication.

Ans: Mobile Computing is a technology that allows the transmission of data, voice and video through a computer or any other wireless enabled devices without having to be connected to a fixed physical link.

Mobile Computing enables people to connect their laptops, tablets etc. to the internet and people can communicate with each from anywhere in the world. It enables people to send emails, audios and videos.

k. What is mobile computing? Explain why it is becoming more popular these days.

Ans: Mobile computing is a technology that allows the transmission of data through any wireless enabled devices. Mobile computing is becoming popular these days because of the following reasons:

• It saves our time.
• It enhance productivity.
• It is a source of entertainment.
• It supports cloud computing.

l. What is a computer system? Explain shortly.

Ans: Computer system is a functional unit in which a group of integrated hardware works together with software to fulfill the purposes of the instructions or program. Basically, it is a system which takes input, process the data and gives meaningful result as an output.

m. Write any five differences between computer organization and computer architecture. 

Ans: The five differences between computer organization and computer architecture are as follows:

Computer Organization	Computer Architecture
It refers to the component from which a computer is built.	It refers to the integrating those components to achieve a level of functionality and performance.
It is implementation of its architecture.	It is the designed construction that may lead to improved system performance.
It is concerned with the way the hardware component operate and the way they are connected.	It is concerned with the structure and behaviour of computer system as seen by user.
It describe how it does it.	It describes what the computer does.
It is like building a house by a brick.	It is like building the design and architecture of the house which takes maximum time.

n. What is a processing unit? Explain its different components.

Ans: A processing unit is the central processing unit of a computer which carries out the instruction of a computer program by performing basic arithmic and logical operations and controlling different components by sending and receiving control signals. 

The different components of processing unit are as follows :

i. ALU
Arithmetic Logic Unit (ALU) is the part of the CPU where all the processing tasks are actually performed. It performs its entire task according to the control signal from the control unit (CU). As required, data that needs to be processed is transferred from the memory unit to the ALU. During the processing, data may move many times from the memory unit to the ALU and back to the memory unit till the processing is completed. 

ii. CU

Class 11 Computer Notes

Control Unit (CU) is responsible for directing and controlling all the components of the computer including input devices, output devices, memory devices, and other components of the CPU. It uses control signal. The control unit receives instructions from the program, decodes them, and generates signals to inform the ALU and other components about the operation that has been requested. It sends signals to input and output devices to perform tasks as instructed.

iii. MU
A memory unit is a temporary storage area within the CPU that stores instructions and data currently being used in the computer. To execute an instruction, the control unit of the CPU retrieves it from the main memory and places it into a register.  Instructions and data must be in registers before they can be executed or processed. It supplies data to the ALU and stores the results of ALU operations.

o. What is a primary memory? List its functions. 

Ans: Primary memory is the main memory of the computer which stores data and instructions to be used by the Computer temporarily.
The function of Primary memory are as follows:

• It stores all the data to be processed and the instructions ons required for processing.
• It stores currently running program. 
• It stores the intermediate result of processing.

p. How is data processed by a microprocessor? Explain with diagram.

Ans: A microprocessor accepts binary data as input, process the data and then provide output based on the instructions stored in the memory. The data is processed using the microprocessor's ALU, CU and MU.

The main steps involved in data processing are given below:

i) The control unit sends a virtual address of the data to the protection test unit.

ii) The protection test unit varies the virtual address of the data and forwards the virtual address to the segment and paging Unit, where it is translated into a physical address to be used by the interface unit.

iii) The interface unit locates the address and retrieves the data back through the protection test unit and stores in the internal registers of the CPU. These registers act as the working memory of the execution unit.

iv) If data involves a mathematical calculation, it is sent to the ALU where the calculations are done.

v) Finally, the control unit tells the bus interface unit to send the processed data back to the RAM for storage.

 

q. What is a system bus? Write the uses of different types of buses.

Ans: A System bus is a facet of computer architecture that transmits and shares data throughout the computer and between devices.

The uses of different types of buses are as follows:

i. Data Bus
It carries the data between the processor and other components. The data bus is bidirectional.

ii. Control Bus 
It carries control signals from the processor to other Components. It also carries the clock's pulses.

iii. Address Bus 
It carries memory addresses from the processor to other components such as primary storage and input/output devices. The address bus is unidirectional.

r. What is computer memory? Write the differences between SRAM and DRAM.

Ans: A computer memory is  a device or a system used to store information, data and programs that is required for processing. The differences between SRAM and DRAM are as follows:

SRAM	DRAM
It has lower access time and is faster than DRAM.	It has higher access time and is slower than SRAM.
It uses transistors.	It uses capacitors and very few transistors.
It is an on-chip memory.	It is an off-chip memory.
It is used for cache memory.	It is used for main memory.

s. What is cache memory? List its advantages and disadvantages.

Ans: A cache memory is a high speed memory that is built into a CPc which lets you to access data more quickly than you access it from computer hard drive. The advantages and disadvantages of cache memory are as follows:
Advantages
It is faster than main memory.
It consumes the less access time as compared to the main memory.
Disadvantages
It has limited capacity. 
It is very expensive.

t. What is a secondary memory? Why does a computer need secondary storage? Explain.

Ans: A secondary memory is the storage device which stores data, information or programs permanently till they are not deleted.

A computer needs secondary storage device inorder to prevent data and information from being lost when we turn off the computer.

u. What are the differences between HDD and SDD?

Ans: The differences between HDD and SDD are as follows:

HDD	SDD
It produces a bit noise when it is used.	It makes no noise at all when it is used.
It is slower than a SSD.	It is faster than a HDD.
It stores data on magnetic disks.	It stores data on flash memory chips.
It is less expensive than SDD.	It is more expensive than HDD.

 

v. What is a printer? Write the differences between impact and non-impact printers.

Ans: A printer is an output device that displays the data or result of processing on paper. The differences between impact and non- impact printers are as follows:

Impact Printer	Non-impact Printer
It is a printer that physically strikes paper.	It is a printer that does not strike the paper.
It is slow and noisy.	It is fast and less noisy.
The printing quality of impact printer is low.	The printing quality of non-impact printer is high.
The operating cost is low.	The operating cost is high.

 

w. What is an output? Differentiate between a CRT monitor and a LCD monitor.

Ans: All the devices that are used sed to display or present the result of processing in human-understandable form is known as output device. The differences between a CRT monitor and a LCD monitor are as follows:

CRT Monitor	LCD Monitor
It is less expensive.	It is more expensive.
It uses more energy.	It uses less energy.
It is heavier and bulkier.	It is lighter and thinner.
It emits harmful radiation.	It does not emits radiations.

 

x. Write short notes on:

i. Analog Computer 
An analog (also called analogue) computer is a special purpose computer that can process only analog data (continuous varying physical quantities like temperature, pressure, speed, depth, height, voltage, etc.). Analog computers can measure analog data and convert them to numeric value. 

ii. Digital Computer
Digital computers are general purpose computers that can perform a variety of tasks. A digital computer uses the binary digits (bits) 0 and 1 to represent discrete data (discontinuous data) like letters, numbers, symbols, and figures. It can process discrete data. It can perform arithmetic, relational, and logical operations.

iii. Microcomputer
A microcomputer is a digital computer that has a microprocessor as its main electronic component. It is also called a Personal Computer (PC). It is a small and powerful single user computer. It supports many higher level languages, multimedia, graphics, 3D graphics, and games. 

iv. Mainframe Computer
Mainframe computers are multi-user computers that have faster processing speed and more storage capacity than minicomputers. They are capable of handling large volumes of data. Mainframe computers support parallel processing. The parallel processing involves combining a large number of processors that break down an application into many separate parts in order to enhance processing speed. 

v. Supercomputer
Super computers are the most powerful computers. They are the fastest and the most expensive. A supercomputer contains a number of microprocessors that operate in parallel to make it faster. They are task specific computers and are used by large organizations for scientific and engineering applications where large databases are processed. 

vi. Versatility
A computer is a versatile machine. It has the capability of doing various kinds of tasks. Due to the versatile nature of a computer, it is used in almost all fields. It can be used for calculation, preparation of documents, designing, researching, and entertaining. 

vii. Bar Code Reader

A Bar Code Reader (BCR) is an input device that reads the Universal Product Code (UPC) of a bar code and transfers it to a computer. A bar code represents data in a set of vertical parallel lines of varying thicknesses with gaps. Books and goods in the market are labeled with bar codes.

viii. Scanner
A keyboard enables a user to input only text through the different keys. The keyboard cannot input pictures, handwritten or printed documents into a computer. A scanner is an input device that can input any graphical image, photo, handwritten or printed document into a computer.

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3. Long answer questions:

a. Explain the features of the computer.

Ans: A computer has different features that are mostly not found on other devices. Some of the main features of Computer are briefly explained below:

i. Automatic
The computer is an automatic machine. Once you have fed instructions to the computer, you don't need to instruct it again and again. It can do the tasks automatically as instructed by a program.

ii. Storage
Computers can store a large volume of data, information, and programs on storage devices like hard disks, optical disks (CD/DVD/blu-raydiscs) and flash drives as files. These devices store data, information, and programs as long as desired by the user and can be used whenever required. The storage capacities (memory size) of such devices are measured in bytes and higher units of bytes. 

iii. Diligence
Since there are no wearing and tearing parts in a computer, it can perform the task repeatedly without losing speed and accuracy for a long time. Due to this characteristic of a computer, it is also called a diligent machine. This capability of the computer makes it useful in quality control and process control tasks.

iv. Versatility
A computer is a versatile machine. It has the capability of doing various kinds of tasks. Due to the versatile nature of a computer, it is used in almost all fields. It can be used for calculation, preparation of documents, designing, researching, and entertaining. It can even be used for transferring E-Mail, E-Fax, messages and files from one computer to another computer in any part of the world.

v. Reliability
A computer is a reliable and dependable electronic device. The accuracy of a computer is 100%, so a person can rely on the information produced by a computer. A computer stores data and information permanently for future uses. Data and information stored in secondary storage devices do not get deleted till a user does not delete them.

b. Describe the applications of computers in different sectors.

Ans: Computer are widely used in different sectors for different purposes. Some of the application of computer in different sectors are described below:

i. Education
Computers are used in educational institutions like schools, colleges, and universities. In educational institutions, computers are used as teaching aids, information resources, and computing and research tools. For the teaching and learning processes, computers are used by teachers and students in schools and colleges. Computers are also used in the administrative sector for keeping records.

ii. Office
Computers are used in offices to keep records of staffs and prepare different kinds of documents, presentations, spreadsheets, etc. Computers are also used in offices for sending or receiving electronic mails (e-mails). Staffs in offices can also use computers for online chatting. It is used to prepare, store and retrieve data as electronic files.

iii. Banking
Nowadays, almost all banks and finance companies are using computers. Computerized banking system has made banking process faster and easier. Computers have been used in banking sector for the following reasons:

• To control the entire baking system.
• To maintain customers' accounts. Computers help to calculate payments, interest and balance amount of customers.
• To supervise the entire banking activities.

iv. Desktop Publishing
Computer is essential for Desktop Publishing (DTP). Using Desktop publishing software like Adobe InDesign, Microsoft Publisher, Affinity Publisher, QuarkXPress, VivaDesigner, Scribus, etc. on a computer brochures, magazines, newspapers, books, etc. are designed and produced. The DTP software makes it easy to prepare sketches, images, diagrams and to apply styles and layout texts and graphics. 

c. Explain the advantages and disadvantages of computers.

Ans: The advantages and disadvantages of computers are given below in the form of points.

Advantages of Computer
Computers have had a very vital impact on society. It has changed the way of life of people. The use of computer technology has affected every field of life. People are using computers to perform different tasks quickly, easily, and in a more organized way. Some advantages of computers are:

• It is always accurate and reliable than humans. 
• It is the fastest device and saves our time and money.
• It is a diligence device and can be used regularly for a long time without losing efficiency and accuracy.
• It can be used for communication among many users.
• It is a versatile machine. It can be used in many different areas to do a lot of different tasks.

Disadvantages of Computer
The use of computers has also created some problems in society, which are as follows.

• It reduces the needs of people and increases unemployment in society.
• It has been used for cybercrimes like hacking, creating and spreading viruses, etc. 
• It makes humans fully dependent on it.
• It makes a person non socialization.
• Repair and maintenance are required frequently.

d. Classify the computers in different generations and explain them in shortly.

Ans: Computer are mainly classified into five generations. They are briefly explained below:

i. First Generation Computers
The computers, which were developed from 1943 AD to 1958 AD with vacuum tubes or valves as the main electronic components, are the first generation computers. Due to the vacuum tubes, they were huge, slow, and expensive. They required a lot of electricity and generated a lot of heat.

ii. Second Generation Computers 
All the computers developed from 1959 AD to 1964 AD with transistors as the main electronic component were the second generation computers. In the second generation computers, transistors were used in place of vacuum tubes as the main components in their circuitry. One transistor could do the work of 1000 vacuum tubes. 

iii. Third Generation Computers
The invention of the integrated circuit (I.C.) in 1958 AD by Jack Kilby and Robert Noyce (founder of Intel Company) led to the foundation of third generation computers. The third generation computers appeared in 1965 AD with the I.C., which is also called the 'Semiconductor Chip'. An IC is a miniaturized electronic circuit that contains a number of transistors ona single wafer of silicon. Due to the use of IC, the third generation computers were more reliable, powerful, and smaller in size.

iv. Fourth Generation Computers 
The fourth generation computers appeared in 1975 AD with microprocessors (i.e. VLSI). The microprocessor or Very Large Scale Integration is an integrated circuit that consists of millions of transistors. The use of microprocessors in computers has made the computers more powerful, efficient, reliable and smaller in size than the computers of previous generations.

v. Fifth Generation Computer 
Fifth generation computers are still in the development stage. The fifth generation computers will be based on biochips or super conductor chips i.e. Ultra Large Scale Integration (ULSI). The fifth generation computers will have artificial intelligence (AI), so they will understand natural language and be capable of thinking themselves. They will have parallel processing capability.

e. Classify the digital computers and explain them.

Ans: Digital computers help users to perform tasks efficiently, conveniently, and in more organized ways. Digital Computer are classified into 4 types which are explained below:

i. Microcomputer
A microcomputer is a digital computer that has a microprocessor as its main electronic component. It is also called a Personal Computer (PC). It is a small and powerful single user computer. It supports many higher level languages, multimedia, graphics, 3D graphics, and games.

ii. Minicomputer
A minicomputer is a general purpose digital computer that can have one or more processors. Minicomputers were developed in 1960s. An early and highly successful minicomputer was PDP-8 which was manufactured by Digital Equipment Corporation (DEC) in 1964 AD. Minicomputers are also known as midrange computers.

iii. Mainframe Computer
Mainframe computers are multi-user computers that have faster processing speed and more storage capacity than minicomputers. They are capable of handling large volumes of data. Mainframe computers support parallel processing. The parallel processing involves combining a large number of processors that break down an application into many separate parts in order to enhance processing speed.

iv. Super Computer
Super computers are the most powerful computers. They are the fastest and the most expensive. A supercomputer contains a number of microprocessors that operate in parallel to make it faster. They are task specific computers and are used by large organizations for scientific and engineering applications where large databases are processed.

f. What is mobile computing? Describe its applications.

Ans: Mobile computing is a technology that allows the transmission of data, voice and videothrough a computer or any other wireless enabled device without having to be connected to a fixed physical link.

Applications of mobile computing Some applications of mobile computing are listed below:

• Email
• Messaging
• Educational services
• Entertainment services
• Web browsing
• E-Commerce 
• Emergency services
• Global position system (GPS)

g. What is a microprocessor? Explain the components of microprocessor.

Ans: A microprocessor is an integrated circuit that contains millions of transistors (i.e. electronic components) packed onto a single chip. It executes instructions of a program, carries out arithmetic and logical operations, and controls other components of a computer. So, it is known as the brain of the computer. The components of computer are as follows:

i. Bus Interface Unit
The Bus Interface Unit (BIU) is the part of the microprocessor that links the CPU with the othe components of a computer. It handles all the transfer of control signals, data and addresses on the buses for the execution unit (EU). It sends out addresses, fetches instructions from memory, reads data from ports and memory, and writes data to ports and memory.

ii. Execution Unit
The execution unit (EU) receives program instruction codes and data from the bus interface unit, executes them, and stores the results in the general registers. It can also store the data in a memory location or send it to an I/O device by passing the data back to the B Since it has no connection with the system buses, it receives and outputs all its data throug BIU.

iii. Prefetch Unit 
The Prefetch unit decides and instructs the bus interface unit to retrieve data and instructions from the main memory (RAM). The prefetch unit queues instructions to assure that the microprocessor is in continuous operation.

iv. Segment and Paging Unit
The segment and paging unit (i.e. memory management unit) converts internal logic addresses into external memory addresses.

v. Decode unit
The decode unit decodes or translates instructions into a simple format understood by the ALU and registers. It makes processing more efficient.

h. What is computer memory? Explain primary and secondary memories.

Ans: Computer memory is a device that stores data, information and programs either temporarily or permanently. Computer memory are classified into primary and secondary memory.

i. Primary Memory
A primary memory is the internal memory of which is also known as main memory. It is a Semi-conductor based computer memory that stores fewer amounts of data. Primary memory is classified into RAM and ROM.

ii. Secondary Memory
A secondary memory is the storage area where information or programs are stored permanently till they are deleted. It is the external memory of the computer which is also known as auxiliary memory.

i. What is a computer system? Explain the components of the computer system.

Ans: A computer system is a functional unit in which a integrated hardware works together with software to fulfill the purpose of instruction or program. The different components of computer system are shortly explained below:

i. Input Unit 
An input unit is the device through which data and instruction are fed in the computer system.

ii. Processing Unit
A processing unit is the central processing unit of computer which process the data entered into the computer by users.

iii. Output Unit 
An output unit is the part of computer system which presents the result of processing and other information.

iv. Storage
A storage is the component of computer system that stores data, information and programs either temporarily for permanently.

j. What is computer architecture and computer organization? Describe the different units of computer system. 

Ans: Computer architecture refers to the conceptual structural design and fundamental operational structure of a computer System. It defines how the different componends of computer system are connected to each other.

Computer Organization refers to the component from which a computer is built. It deals with physical aspect of computer like circuit design, memory and its types etc.

The different units of computer system are as follows:

• Input Unit
• Central Processing Unit
• Memory Unit
• Output Unit

k. Define computer architecture? Draw a block diagram of the computer system along with logical connections. Explain each block in detail.

Ans: Computer architecture refers to the conceptual structural design and fundamental operational structure of a computer system. In other words, it is the conceptual design of different components of a computer system and it defines how the different components of the computer system are connected to each other.

 

Input Unit
An input unit is a device through which data and instructions are fed into the computer system. It is a medium through which a user communicates with a computer. The input unit converts data and instructions in human understandable form into computer understandable form and passes them to the computer system.

Processing Unit
A processing unit is the central processing unit (CPU) of a computer. The CPU is one of the important components of the computer system. It is also called a processor or microprocessor. It is an integrated circuit containing millions of transistors packed onto a single tiny chip.

Arithmetic Logic Unit (ALU)
Arithmetic Logic Unit (ALU) is the part of the CPU where all the processing tasks are actually performed. It performs its entire task according to the control signal from the control unit (CU). As required, data that needs to be processed is transferred from the memory unit to the ALU.

Control Unit (CU)
Control Unit (CU) is responsible for directing and controlling all the components of the computer including input devices, output devices, memory devices, and other components of the CPU. It uses control signal.

Registers
A register is a temporary storage area within the CPU that stores instructions and data currently being used in the computer. To execute an instruction, the control unit of the CPU retrieves it from the main memory and places it into a register.

Primary Memory 
A computer memory is just like a human brain. It is the part of the computer that stores data, information, instructions, or programs either temporarily or permanently. 

Secondary Memory
A secondary memory or secondary storage device is the storage area where data, information or programs are stored permanently till they are not deleted. It is the external memory of a computer and is also known as auxiliary memory.

Output Units
All the units that are used to display or present the result of processing and other information to the user in a human-understandable form are known as output units. A monitor and a printer are the most commonly used output devices. Some other output devices are speakers, projectors, and plotters.

l.  Explain the role of memory in a computer and differentiate between main memory and auxiliary storage.

Ans: Memory is one of the main requirement of computer system. It is needed for a computer to store, data and instructions.  

The difference between primary memory and auxiliary memory are as follows:

Main Memory	Auxiliary Memory
It is the internal memory of computer.	It is the external memory of computer.
CPU can directly access data from main memory.	CPU can't excess data of auxiliary memory directly.
They are more expensive than auxiliary memory.	They are less expensive than main memory.
It stores data temporarily.	It stores data permanently.

 

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4. Write the full forms of the following:

a. MIPS = Millions Instructions Per Second 
b. GIGO = Garbage In Garbage Out
c. ATM = Automated Teller Machine 
d. SMS = Short Message Service 
e. VOIP = Voice Over Internet Protocol 
f. GPS = Global Positioning System 
g. SSI = Small Scale Integration 
h. MSI = Medium Scale Integration 
i. VLSI = Very Large Scale Integration 
j. ULSI = Ultra Large Scale Integration 
k. BIT = Binary Digits 
l. Al = Artificial Intelligence