This document provides an overview of computer components and how they work. It describes the main types of computers as microcomputers, minicomputers, mainframes, and supercomputers. It then explains the basic components of a computer system including input devices like keyboards and mice, processing devices like the CPU, output devices like monitors and printers, and storage devices like RAM, ROM, hard disks, CDs/DVDs. It outlines the basic functions of computers as taking input, processing it, and providing output. Finally, it distinguishes between application software like word processors and system software like operating systems.

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COMPUTER

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TYPES OF COMPUTER........................................................................... 4
MICRO COMPUTERS .......................................................................... 4
MINI COMPUTERS............................................................................. 4
MAINFRAME COMPUTERS..................................................................... 4
SUPER COMPUTERS .......................................................................... 4
HOW A COMPUTER WORKS? .................................................................... 4
TYPES OF COMPUTER SYSTEM:-................................................................ 5
HARDWARE ..................................................................................... 5
INPUT DEVICES- ................................................................................ 5
KEYBOARD-................................................................................... 5
MOUSE-....................................................................................... 6
MICROPHONE-................................................................................ 6
DIGITAL CAMERA- ............................................................................ 6
WEBCAM-..................................................................................... 6
PROCESSING DEVICE............................................................................ 7
OUTPUT DEVICE................................................................................ 7
MONITOR- .................................................................................... 7
PRINTER-........................................................................................ 7
 DOT MATRIX PRINTER................................................................... 8
 INKJET PRINTER......................................................................... 8
 LASER PRINTER.......................................................................... 8
SPEAKERS AND HEADPHONES- ............................................................... 9
STORAGWE DEVICES............................................................................ 9
PRIMARY MEMORY DEVICES-.................................................................... 9
RAM (RANDOM ACCESS MEMORY)............................................................ 9
ROM (READ ONLY MEMORY)................................................................. 10
SECONDARY MEMORY DEVICES- ............................................................... 10
CD AND DVD................................................................................. 10
PEN DRIVE................................................................................... 10
MEMORY CARD .............................................................................. 10

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HARD DISK................................................................................... 10
SOFTWARE..................................................................................... 11
TYPES OF SOFTWARE ....................................................................... 11
APPLICATION SOFTWARE...................................................................... 11
SYSTEM SOFTWARE............................................................................ 11
KNOW
YOUR
COMPUTER

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KNOW YOUR COMPUTER
Computer is an electronic device for storing and processing
data. A computer is also called a computer system. It can do a
variety of jobs for us.
TYPES OF COMPUTER
 MICRO COMPUTER
 MINI COMPUTER
 MAINFRAME COMPUTER
 SUPER COMPUTER
MICRO COMPUTERS
Micro computers are smaller in size and capabilities. They are generally used in schools,
offices, shops, etc. to do various types f jobs. They are the most popular and multipurpose
computers. These computers are cheapest as compared to mainframe computers, mini
computers and super computers.
Micro computer is also called Personal computers (PCs).EXAMPLES are Desktops, laptops
and tablets.
MINI COMPUTERS
Mini computers are more capable than micro computers. They are faster and have more
storage capacity than the micro computers. These computers are used less these days.
EXAMPLES are PDP-11, K-202 etc.
MAINFRAME COMPUTERS
Mainframe computers are more capable computers. These are large in
size, faster and quite expensive than mini computers. These are
mostly used by large organizations where large amount of data needs
to stored, such as banks, railways, etc. EXAMPLES are ICL 39, IBM
4381 etc.
SUPER COMPUTERS
Super computers are more powerful computers. They are very
expensive. They are used in forecasting weather, controlling
satellites, studying earthquakes, etc. EXAMPLES are Cray X-MP, PACE
etc.
HOW A COMPUTER WORKS?
A computer takes data from the user, processes it according to the instruction and then
gives back the information as result to us. This means that a computer follows three
stages:-

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 INPUT: The values, facts and instructions given by us is called the input.
 PROCESS: The calculations and comparisons done by CPU is called the processing.
 OUTPUT: The result given by the computer after processing is called the output.
TYPES OF COMPUTER SYSTEM:-
HARDWARE
All the physical parts of a computer which can be seen or touched are called hardware.
The hardware parts are further classified into input devices, processing devices, output
devices and storage devices.
INPUT DEVICES-
The parts of computers we use to feed data and instructions to it are called input devices.
Some of the input devices are:-
KEYBOARD-
A keyboard is used to feed data
and instructions by pressing its
keys. It has many types of keys
each having a different role.
INPUT PROCESS OUTPUT
COMPUTER
SYSTEM
HARDWARE
INPUT
DEVICES
PROCESSING
DEVICE
OUTPUT
DEVICES
STORAGE
DEVICES
SOFTWARE
APPLICATION
SOFTWARE
SYSTEM
SOFTWARE
KEYBOARD

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MOUSE-
A mouse is used to feed data and instructions by clicking its
buttons. Now a days, OPTICAL and LASER mouse are the most
popular. A mouse may be fixed to the CPU box or may be
Wireless.
MICROPHONE-
A microphone is used to record voice and music into a computer.
DIGITAL CAMERA-
A digital camera stores captured photos in a removable memory card
which is fixed inside the camera. The images in the card can be
transferred as input to the computer.
WEBCAM-
A webcam captures photos and stores directly on the computer.
It is connected to a computer so there is no memory card
required. Some laptop have a webcam fixed inside it.

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PROCESSING DEVICE
The CPU (Central Processing Unit) is the processing device. It is fixed inside the CPU box.
It processes and stores the data and instructions given by us. It controls all INPUT and
OUTPUT DEVICES.
OUTPUT DEVICE
The parts of a computer that give the information (result after processing) are called
output devices.
MONITOR-
A monitor displays the output (texts, pictures or videos) on it. The output we get on the
monitor is also called SOFTWARE.
It is common output device. It is known as VDU ( visual display unit)
CRT MONITOR LCD MONITOR
PRINTER-
A printer gives the output (text and pictures) on a paper. The printer copy is HARDCOPY.
Moniter
LCD (Liquid
Crystal Display)
CRT (Cathode
Ray Tube)

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 DOT MATRIX PRINTER
1. Print only in black in color.
2. Make a lot of noise while printing.
3. Can print only a few pages in a minute.
 INKJET PRINTER
1. Print in color also.
2. Make very less noise while printing.
3. Can print many pages in a minute.
 LASER PRINTER
1. Print in color also
2. Make very less noise while printing
3. Can print up to 100 pages in a minute
4. Best in quality
PRINTER
DOT MATRIX
PRINTERS
INKJET
PRINTERS
LASER
PRINTERS

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SPEAKERS AND HEADPHONES-
Speakers and Headphones are used to listen to music
and songs as output from the computer.
Speakers give out loud sound, while Headphones are
used by an individual without letting others to get
disturbed with the sound.
STORAGWE DEVICES
The parts of the computer we use to store work are called STORAGE DEVICES. They are
called MEMORY DEVICES.
PRIMARY MEMORY DEVICES-
It is a main memory of the computer. It present inside the CPU. We cannot access the
primary memory.
RAM (RANDOM ACCESS MEMORY)
It stores data temporarily while the computer is
working. It is a temporary memory because the data
gets erased when the computer is switched OFF.
PRIMARY
MEMORY
SECONDARY
MEMORY
STORAGE
DEVICES

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ROM (READ ONLY MEMORY)
It stores the instructions given by the manufacturer to operate
the computer. It is a permanent memory.
A MOTHERBOARD IS THE MAIN CIRCUIT BOARD INSIDE A CPU THAT HOLDS THE
INTERNAL PARTS OF THE COMPUTER, SUCH AS CPU, RAM,ROM ,HARD DISK, ETC.
SECONDARY MEMORY DEVICES-
The storage devices store data and information for a longer period of time.
CD AND DVD
CD stands for Compact Disc and DVD stands for Digital
Versatile Disc. These are portable devices that can store data
and information. We can carry our stored work. The storage
capacity of a DVD is higher than a CD.
PEN DRIVE
A pen drive is small in size like a thumb. We can store work and
carry it in our pocket. Pen drive is called USB DRIVE. Its storage
capacity is higher than a DVD.
MEMORY CARD
It is a removable storage device that is usually fixed inside a mobile
phone, tablet computer or a digital camera. It comes in different storage
capacities that can even be same to that of a pen drive
HARD DISK
It stores all the software, data and information. It is fixed inside the
CPU box. It has the largest storage capacity. Nowadays , external hard
disk are also available in the market.

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Earlier FLOPPY DISKS were used as storage devices.
Their capacity was very less.
SOFTWARE
A set of instructions given to a computer to make it work are called SOFTWARE. Hardware
need instructions to work.
TYPES OF SOFTWARE
APPLICATION SOFTWARE
An application software is also called an app. This software does a specific type of work.
For example- Paint app for drawing, Word app for typing, etc.
SYSTEM SOFTWARE
This software controls the overall working of a computer.
For example- Operating system (without operating system we cannot even start the
computer.)
TYPES OF
SOFTWARE
APPLICATION
SOFTWARE
SYSTEM
SOFTWARE

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THANK
YOU
JASVINDER KAUR
1ST
YEAR
SECTION - B