1. Vacuum tubes were the only electronic components available during
2. Vacuum tube technology made possible the advent of electronic
3. These computers were the fastest calculating devices of their time.
1. To bulky in size.
3. Air conditioning required.
1. Smaller in size as compared to first generation computers.
2. More reliable.
3. Less heat generate.
1.Frequent maintains required.
2. Manual assembly of individual components into a functioning unit
3. Commercial production was difficult and costly.
1. Smaller in size as compared to previous generation computers.
2. Even more reliable then second generation computers.
3. Even lower heat generated tan second generation computers.
1. Air conditioning required in many cases.
2. Highly sophisticated technology required for the manufacture of IC
1. Smallest in size because of high component density.
2. Very reliable.
3. Heat generated is negligible.
1. Highly sophisticated technology required for the manufacture of
1. A noninvasive probe that provides painless probing to the
2. Guidance path is predetermined.
3. Computer shortage of data and printout or visual can be used
for patient education.
2. Operator needs to understand the images provided by the
3. Requires a learning curve.
Block Diagram of Computer
Characteristics Of Computer
4- Storage Capacity
6- Reduction in man power
7- Reduction in paper work
8- Never gets tired
Application Areas Of Computer
1- Banks 12- Criminal Identification
2- Defense 13- Automation
3- Research 14- Sports
4- Education 15- Shopping Complex
5- Communication 16- Medical Sciences
6- Weather Forecasting 17- Government Centers
7- Media 18- Electronic Voting System
8- Edutainment 19- Hotels & Restaurant
9- Business 20- Airlines/Railways Reservation
10- Animation & Films 21- Library
11- Book Publishing
Functioning Of Computer
(i) Input- Computer accepts the input given by the user it can be in
the form of instructions or commands to do computer to operate on
the data it could be a single command to do a task or a set instructions
to preforms a series of steps this set of instructions is called a
(ii) Storage and Retrieval- The input is stored in the memory of
computer and it can be Retrieved whenever required.
(iii) Processing- The execution of instructions given to the computer
is called processing.
(iv) Output- Final result or output, available to the user, either on the
monitor (soft copy) or as a print out (hard copy) is called output.
Bar Code ReaderJoystick
Fastness Of C.P.U
Fastness of C.p.u depends on the
Processor . The speed of C.P.U is
determine by the number of
instructions executed per second
1. It is an Electronic board found at the bottom of the
2. It is the largest circuit board.
3. A Motherboard has a processor chip, memory chips and
many other logic circuits.
4. It is also called system board, and it is the most
important computer hardware.
Processor is a chip where a large
number of circuit elements are
integrated onto a very small piece
e.g. : Intel
1. This unit controls of each and every component of
the computer system.
2. It controls the transfer of data and instructions
among other units of computer.
3. It is also called the Central Nervous System of
1.RAM [Random Access Memory]
It is a volatile memory as instruction and data stored temporarily,
during its processing and lost forever when the computer is switched
2.RAM [Random Access Memory]
(i) It is non-volatile memory as it stores information. Permanently and
cannot be changed.
(ii) The primary use of ROM is during booting.
BOOTING: It is initial program to start up the computer, when power
is switched on.
3. Cache Memory
It is a special high speed memory.
It stores frequently used instruction, so that the CPU can access them
quickly and easily.
Units Of Memory
Nibble- Group of 4-bits
Byte- Group of 8-bits
Kilo Byte- 1KB=1024 bits
Mega Byte- 1MB=1024 KB
Giga Byte- 1GB= 1024 MB
Tera Byte- 1TB= 1024 GB
Software- The set of information when executed in a particular sequence
perform. The collection of such types of programs are called software.
Software increases capability of hardware and directs the computer
to perform operations like inputs, processing and output.
Its acts as
between user and
It is collection
of one or
It is installed by
Its designed to control
the overall operations
and performance of the