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1. 1. Data Information

2. Content
 Introduction
 Transforming data into information
 Data representation in Computer
 Summary

3. Introduction
 The computer accepts data as an input, stores it
process it as the user requires and produces
information or processed data as an output in
desired format.
 Computer is one of the major component of an
Information Technology and is gaining increasing
popularity.
 Basic Computer operations:
 It accepts data or instruction by way of input.
 It stores data.
 It can process data as required by the user.
 It gives result in form of output .
 It controls all operations inside a computer.

4. Transforming data into information
The process of producing results from the data for getting useful
information can be termed as Transforming Data Into
Information.

5.  What is Data?
Data can be defined as a representation of facts, concepts or
instruction in a formalized manner which should be suitable
for communication , interpretation or processing by human or
electronic machine.
Data is represented with the help of characters like alphabets
(A-Z, a-z), digits (0-9) or special characters(+,-,/,*,<,>,= etc).

6.  What is Information?
 Information is organized or classified data so that it has some
meaningful values to the receiver. Information is the processed
data on which decisions and actions are based.
 For the decision to be meaningful, the processed data must
qualify for the following characteristics
 Timely - Information should be available when required.
 Accuracy - Information should be accurate.
 Completeness - Information should be complete.

7.  DATA PROCESSING:
 Data processing is the re-structuring or re-ordering of data
by people or machine to increase their usefulness & add
values for particular purpose.
 Data processing consists of basic steps input, processing
and output. These three steps constitute the data processing
cycle.

8. Data Processing Cycle

9.  Input –
In this step the input data are prepared in some convenient form for processing.
The form will depend on the processing machine. For example, when electronic
computers are used, the input data could be recorded on any one of several types
of input medium, such as magnetic disks, tapes and so on.
 Processing –
In this step input data are changed to produce data in a more useful form. For
example, pay-checks may be calculated from the time cards, or a summary of sales
for the month may be calculated from the sales orders.
 Output –
Here the result of the proceeding processing step are collected. The particular
form of the output data depends on the use of the data. For example, output data
may be pay-checks for employees.
 Storage –
Finally the storage unit is used to store data or information permanently.

10. Basic Computer Operations

11. Transforming data into information
 Functional Units
 The computer system is divided into three separate units for its
operation. They are:
 Arithmetic Logical unit
 Control Unit
 Central Processing Unit

12. Transforming data into information
 Functional Units
 Arithmetic Logical Unit {ALU}:
 After you enter data through input device it is stored in the
primary storage unit.
 The actual processing of the data and instruction are
performed by Arithmetic Logical Unit.
 Operation performed by the ALU are:
 Addition
 Subtraction
 Multiplication
 Division
 Logic
 Comparison

13. Arithmetic Logical Unit (ALU)

14. Transforming data into information
 Functional Units
 Control Unit (CU):
 Acts like the supervisor seeing that things are done in proper
fashion.
 Determines the sequence in which computer programs and
instructions are executed.

15. Control Unit

16. Transforming data into information
 Functional Units
 Central Processing Unit (CPU):
 The ALU and the CU of a computer system are jointly known as
the central processing unit.
 CPU can be called Brain of any computer system.
 It takes all major decisions, makes all sorts of calculations and
directs different parts of the computer functions by activating and
controlling the operation.

18. Data representation in Computer
 Instruction data representation considers how a
computer uses numbers to represent data inside the
computer.
 Three types of data are considered at this stage:
 Number including positive , negative and fractions
 Text
 Graphics

19. What is Computer
Number System?

20. COMPUTER -NUMBER SYSTEM
 When we type some letters or words, the computer
translates them in numbers as computers can
understand only numbers.
 A computer can understand positional number system
where there are only a few symbols called digits and
these symbols represent different values depending on
the position they occupy in the number.
 A value of each digit in a number can be determined
using
 The digit
 The position of the digit in the number
 The base of the number system (where base is defined as the total
number of digits available in the number system).

21.  Decimal Number System
 The number system that we use in our day-to-day life is the
decimal number system. Decimal number system has base
10 as it uses 10 digits from 0 to 9. In decimal number
system, the successive positions to the left of the decimal
point represent units, tens, hundreds, thousands and so on.
 Each position represents a specific power of the base (10).
 For example 1234 can be written as:
(1x1000)+ (2x100)+ (3x10)+ (4xl)
(1x103)+ (2x102)+ (3x101)+ (4xl00)
1000 + 200 + 30 + 1
1234

22.  As a computer programmer or an IT professional,
you should understand the following number
systems which are frequently used in computers.
S.N. Number System & Description
1 Binary Number System
Base 2. Digits used: 0, 1
2 Octal Number System
Base 8. Digits used: 0 to 7
3 Hexa Decimal Number System
Base 16. Digits used: 0 to 9, Letters used: A- F

23.  Binary Number System
 Uses two digits, 0 and 1.
 Also called base 2 number system
 Each position in a binary number represents a 0 power of
the base (2). Example 20

25.  Octal Number System
 Uses eight digits, 0,1,2,3,4,5,6,7.
 Also called base 8 number system
 Each position in a octal number represents a 0 power of the
base (8). Example 80

27.  Hexadecimal Number System
 Uses 10 digits and 6 letters, 0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F.
 Letters represents numbers starting from 10. A = 10. B = 11, C
= 12, D = 13, E = 14, F = 15.
 Also called base 16 number system
 Each position in a hexadecimal number represents a 0 power
of the base (16). Example 160

29. Data representation in Computer
 Decimal representation in computers
Decimal Binary coded decimal
0 0000
1 0001
2 0010
3 0011
4 0100
5 0101
6 0111
7 1000
8 1001
9 00010000
10 00010001
11 00010010
12 00010011

30. Data representation in Computer
 Alphanumeric Representation
 A set containing alphabets (in both cases), the decimal digits (1
0 in number) and special characters (roughly 10-15 in numbers)
consist of at lea 70-80 elements. One such code generated for
this set and is popularly used is ASCII (American National
Standard Code for Information Interchange).
 This code uses 7bits to represent 128 characters. Now an
extended ASCII is used having 8-bit character representation
code on Microcomputer.
 Binary codes can be formulated for any set of discrete elements.

31. Data representation in Computer
 Computational Data Representation
 The computer is discrete digital and store information in flip-
flops, which are two state devices, in binary form.
 Basic requirements of the computational data representation
in binary form are:
 Representation of sign
 Representation of magnitude
 If the number is fractional then binary or decimal point and
exponent.
 The solution to sign representation is easy, because sign can be
either positive or negative, therefore, one bit can be used to
represent sign. By default it should be the left most bit.

32.  A number of n bits can be represented as n+1 bit number, where
n+1th bit is the sign bit and rest n bits represent its magnitude.
 To simplify the representation aspect two methods are suggested:
 A) Fixed point representation
• The fixed-point numbers bit 1 binary uses a sign bit. A positive number
have a sign bit 0, while the negative has a sign bit 1. In fixed-point
numbers we assume that the positive of the binary point is at the end.
 B) Decimal Fixed point representation
• A decimal digit is represented as a combination of four bits; thus, a four
digit decimal number will require16 bits for decimal digits
representation and additional 1 bit for sign.
 C) Floating point representation
• The first part of the number is a signed fixed point number, which is
termed as mantissa and the second part specifies the decimal or binary
point position and is termed as an Exponent.

33. Summary
 The five basic operations that a computer performs. These are
input, storage, processing, output and control.
 A computer accepts data as input, stores it, processes it as the
user requires and provides the output in a desired format.
 Computer system into three functional units i.e. Arithmetic
logical unit (ALU), Control unit (CU), Central processing unit.
 Number System