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Introduction to Data
Data is defined as the set or collection of facts and
figures or any thing which can be fed to Computer is called data.
Facts
Data, which can’t be entered with the help of keyboard, can
be called facts e.g. movies, songs, diagrams, maps, pictures etc.
Figures
Data, which can be entered with the help of keyboard, can be
called figures. Figure data can be divided into three types:
1)
Alphabetic Data
2)
Numeric Data
3)
Alphanumeric Data
1) Alphabetic Data
Alphabetic Data consists of alphabets (A-Z).
e.g. Haroon is very good boy.
2) Numeric Data
Numeric Data consists of numbers (0-9) and special
characters (symbols). e.g. 5+5=10
3) Alphanumeric Data
Alphanumeric Data consists of both alphabetic and numeric
data. e.g. Khalid Ph. No=621446
Introduction to Data Processing
To arrange data into a useful form is called data
processing. We do it through Computer.
Information
To process data into a usable
form is called information. Thus the conversion of raw facts into a useable
form is known as information.
Data Processing Cycle
Data processing cycle has three basic steps. These are:
1)
Input Cycle
2)
Processing Cycle
3)
Output Cycle
Input ŕ Processing ŕ Output
Input Cycle
Every source of data entered to Computer by user is called
input cycle.
Input Devices
Devices used to enter data to Computer are called input
devices.
Processing Cycle
After entering the data to Computer, Computer processes it
to give us result/output. This step is called processing cycle.
Processing Unit
Parts of Computer where processing takes place are called
processing unit.
Output Cycle
Once data is entered and processed, the results are to be
brought out for the user. This is called output cycle.
Output devices
Devices used to give us results/information are called
output devices.
Types of Data Processing
Data processing consists of four types:
1)
Manual Data Processing
2)
Mechanical Data
Processing
3)
Electromechanical Data
Processing
4)
Electronic Data
Processing
1) Manual Data
Processing
When all the operations are done manually (by human beings)
on data are called manual data processing.
2) Mechanical Data
Processing
When non-electronic machines like typewriters are used for
data processing is called mechanical data processing.
3) Electromechanical
Data Processing
When simple electronic machines or non-programmable machines
do data processing is called electromechanical data processing.
4) Electronic Data
Processing
It is the manipulation of raw facts using full automatic
electronic machines like Computers. The main purpose of electronic data
processing is to do a complex job of processing in short time. Electronic data
processors process the instructions defined by the programmer.
Bit
Bit is the abbreviation of “Binary Digits” which is either
“0” or “1” (0=OFF and 1=ON). Bit is the smallest unit in the field of data
processing. In Digital Computers all the processing is done in the language of
bits, which is the mother language of the Computer.
Byte
Combination of eight bits forms a byte. It is the basic unit
of data because Computer storage is based on bytes. One byte is equal to one
character.
8 Bits = 1B (Byte)
1024 B = 1 KB (Kilo-Byte)
1024 KB = 1 MB (Mega-Byte)
1024 MB = 1 GB (Giga-Byte)
File
Considering our daily school/college life, we say it is my
Physics copy, English copy etc. Similarly in Computers copy is actually called
file, in which we save, type, record our data, notes, applications, letters
etc. Each file has its own name. These files are named according to our
requirements.
Executable Files
Files used to start any program are called executable files.
Command
Set of instructions given to computer to perform special
function is called command.
Program
A program is set of instructions written in a certain
language. The programs written by a Computer user are called user programs.
Software
The programs used to run Hardware (or a Computer) are called
Software.