Computer Fundamentals DAY 1

In this session you will be able to learn……An introduction to computer

Basic Operation of a computer

Input Devices

Storing Units

Processing Unit

Output Devices

Software & Hardware

Desktop , Palmtop and Laptop Computers

Prepared By – Ajit kumar

Computer • A computer is an electronic device that accepts, stores and

output data high speeds.

MonitorCD Rom Drive

speaker Floppy d

rive

This

is th

e ca

se w

hich

con

tain

s th

e ce

ntra

l pr

oces

sing

unit

Mouse

Key board

Basic operations of a computer

• A computer is nothings but a combination of several non living physical components . Whenever all those physical components (called hardware) in combination give an output than it is a computer . Let us take a look of the above picture of a computer. It is consists of a several Hardware components like keyboard, mouse, speaker, monitor, CPU, Hard disk, Floppy, CD Rom etc. and the functions of all these parts are quite different. If you analyze all the physical parts of a computer you will be notice some devices are for inputting data, some for storing data, some are for processing and some for outputting. Naturally whatever is your computer system consists of; they just perform the following four basic operations.

• Inputting:- The processes of entering data and instructions into the computer system. Inputting is done by the Input Devices. Example of some input Devices are:- keyboard, mouse, sound card ,video capture card, Digital camera , Joystick, Light and pen etc.

• Storing:- Saving data and instructions so that they are available for initial or for additional processing as when required is known as storing. Computer store all data in to its memory. We will discuss computer memory in details in later section.

Processing • Performing arithmetic operations or logical

operations (comparisons like equal to less than, grater than etc.) on data in order to convert them into useful information. Processing is done by the computer processor. Some processor names are Pentium III, Pentium IV etc.

• OUTPUTING:- The process of producing useful and processed information or result for the user, such as a printed report or visual display. For outputting computer uses several output devices like monitor, printer, speaker.

• INPUT DEVICES:- Input devices are used to put data and instructions into the computer. There are many different types of input devices and here are some of them.

KEYBOARD

• Keyboard:- keyboard is found on computers like desktops and note books. Its layout is very similar to a type writer. It is use for a wide range of tasks. It is use for typing in data from paper documents such as applications forms which people have filled in. it is also used for entering different types of data.

MOUSE

• MOUSE:- A mouse is a pointing input device that work

upon GUI(Graphic user interface)platform. Whenever you move

mouse arrow pointer also moves according to the direction you

are moving .this pointer is used to perform different tasks

associated with the mouse.

TOUCH PAD

• TOUCH PAD:- This device is use on laptop computers . Instead of moving a mouse , you control the movement an object on the screen the pad. The pointer moves across the screen in the direction you move your finger . If you tab the touch pad this has the same effect as clicking the mouse. There are also buttons on a mouse.

JOYSTICK

• JOYSTICK:-A joystick is used mainly in computers games. you control the movement of an objects on the screen by moving the joystick. It has tracker ball.

Digital Camera

• DIGITAL CAMERA :- Digital cameras are used to take photographs . Digital camera is look like ordinary cameras but they do not use a film.insted,each camera contains memory just like the CPU of a computer.

SCANNER

• SCANNER:- A scanner is used to make a copy of what is on paper and store it in the computer. It does not mater what is on the paper, whether it is a picture, text even bar codes. An example is the use of a scanner to copy photographs into desk top publishing software as part a different magazine.

STORING DEVICES

The data and instructions that are entered into the computer system through input units have to be stored inside the computer before the actual processing starts. For storing computer uses its memory. Computer memory divided in to two parts.

(A)Primary or main memory(B)Secondary or Backing storage

(A) PRIMARY OR MAIN MEMORY:-Main memory of a computer is a general term for any type of computer memory other than backing storage(secondary storage devise).

(B)Secondary or Backing storage

• Secondary Memory:- Secondary memory is used as permanent storage for programs and data in a computer system . Backing storage is also called secondary storage or mass storage.

Main memory consists of a (RAM)Random Access Memory AND (ROM) Read Only Memory

Random Access Memory

• Random access memory is a type of computer memory which holds its data as long as the computer is switched on. When the computer is switch off, any data held in RAM is lost. RAM is volatile memory.

•Read only memory is a type of computer that hold permanently . Data held in ROM can be read by the CPU in any order.ROM is there for another type of direct access medium.

Storage units:

• Computers use the binary system because it is easy to represent

the two states “on” and “off” inside a computer.

4 Bits= 1 Nibble8 Bits= 1 Bytes1024 bytes= 1 Kilobyte (KB)1024 KBs= 1 Megabyte (MB)1024 MBs= 1 Gigabyte(GB)1024 GBs=1 Tera Byte (TB)

HARD DISKS

• A hard disk(commonly know as a HDD(hared disk drive)or(HD) and formerly known as a fixed disk)is a nonvolatile storage devise which store digitally encoded

data on rapidly rotating platters with magnetic surfaces.

• OPTICAL:- Optical storage media includes CD-ROM (compact disk –Read only memory) CD-R(compact Disk Recordable),CD-RW(compact Disk Re writable),Together with DVD-ROM(Digital Versatile Disk),DVD-Vide o, DVD Audio, DVD-R(Digital versatile Disk Recordable)and DVD-RAM.

CENTRAL PROCESSING UNIT (CPU)

• The CPU is the brain of a computer and consists of 3 main parts: the control unit the arithmetic and logic unit (ALU) and the main memory .

• CENTRAL PROCESSING UNIT (CPU)

Control unit coordinates the whole operation of the computer. It fetches instruction from main memory, processes them and executes the necessary action

Arithmetic and logic unit Performs the Arithmetic and the logical operations such as AND and OR

Main memory Contains data and instrucations.Also know as

the immediate access store for primary store

ProcessorSince there are no moving parts, the processor Perform its functions at incredibly high speeds.