It is a topic related to computer science and many other courses.It will tell you in detail that how a computer transforms data into information and make data meaningful and useful.
3. The
Difference
between
Data and
Information
Data
• Data is unprocessed raw facts
about a particular entity.
• Data is used as input in the
computer.
• Data is not meaningful.
• Data is normally huge in its
volume.
• Data is the asset of
organizations and is not
available to people for sale.
• Data is used rarely.
• Data is an independent entity.
• Data is not used in decision-
making.
• Processing can be applied on
data.
• Data is difficult or even
impossible to reproduce. For
examples, if Government lose
the data of census, if will be
almost impossible to
reproduce it.
Information
• Information is processed
form of data.
• Information is the output of
the computer.
• Information is meaningful.
• Information is normally
short in its volume.
• Information is normally
available to people for sale.
• Information is used
frequently.
• Information depends on
data.
• Information is very
important for decision-
making.
• Processing can not be
applied on information.
• Information is easier to
reproduce if lost. For
example, if the list of
illiterate citizens is lost, it
can be reproduced easily
because the data is still
stored.
5. Number
System
o Numbers are the numbers,alphabets,punctuation
marks and sounds,etc for a computer.
o Computer uses a number system to represent the
data.
o A number system is a way to represent
numbers.computer uses the base-10 number
system, which is also called decimal. Other
common number systems include base-16 (hexa
decimal), base-8 (octal), and base-2 (binary).
7. Bits and Bytes
• Computer represents data in bits and
bytes.
• Computer understand only 0 and 1.
• Bit are the smallest unit to represent
data.
• Collection of 4 bits is called a nibble.
• Collection of 8 bits is called a byte.
8. Text Code
• Computer also uses text codes (is a human-readable sequence of
characters and words,computer form that can be encoded into computer-
readable formats) to represent data .
Types of computer text code:
• EBCDIC
• ASCII
• Extended ASCII
• Unicode Worldwide Character Standard
9. Continue.....
EBCDIC:
• IT stands for Extended Binary Coded Decimal Interchange Code.
• It uses eight- bit codes.
• It is used primarily in older mainframe systems.
• It represents 256 symbols.
ASCII:
• It stands for American Standard Code for Information Interchange.
• It is the most common text-code set.
• It consists of eight bits (one byte) of data.
• ASCII is used in nearly all personal computers.
• It represents 0 to 127 symbols.
Unicode text-code:
• In this set, each character consists of 16 bits (two bytes) of data.
• Specifies the characters for values from 128 to 255.The first 40
symbols represent pronunciation and special punctuation.The
remaining symbols are graphic symbols.
11. Central processing unit (CPU)
• It is the brain of computer.
• It is also called processor.
• It is the most important component of the
computer.
• Computer cannot work without CPU.
• It is located on the mother board.
• It carries out most of the work of a computer.
There are two parts of CPU:
• Arithmetic and logical Unit (ALU)
• Control Unit (CU)
12. Arithmetic and logical Unit (ALU)
Arithmetic Unit
Arithmetic unit perform basic arithmetic unit such as
addition, subtraction, multiplication and division.It is
consist of Arithmetic Circuits.
Arithmetic Circuit:
Adder:
• It is device use to perform addition of two numbers.
• It part of ALU.Some ALU contain multiple adders.
Subtractor:
• To subtract adder is modified.
• It takes 2’s complement of number and add in the
original to subtract a number.
Logical Unit
• It performs logical operation. It is used to compare
two values / data.Such as less than, greater than, less
than equal, greater than equal, equal, not equal
Logical Circuit:
They are used to compare values.Logical circuit consist
of AND, OR NOT gates.It is easy to employ logic
circuit with these operations.
• AND:
• It is a circuit which give output 1 if and only if all
inputs are 1.
• It gives output 0 if any of input is 0.
• OR:
• It is a circuit which gives output 1 if even a single
input is 1.
• It gives output 0 is all inputs are 0.
• NOT:
• It is a circuit which converts 0 into 1, and 1 into 0.
13. Control Unit
It is like the supervisor of the computer.
It does not process data himself,But it controls all
activities of computer system.
It fetches instruction from main memory.
It interrupts (decode) the instruction to find what
operation is to be performed.
It controls the execution of instruction.
14. MEMORY UNIT
It is a component in computer to store data
and instruction.
CPU has its own memory to store data and
instruction at the time of execution.This is
called memory unit (MU) or CPU Registers.
It is the fastest storage area in the computer.
They are available in different sizes like 8,
16, 32 and 64 bits.
15. Machine Cycles
• Each time the CPU executes an
instruction, it takes a series of steps.The
completed series of steps is called a
machine cycle.
• A machine cycle itself can be broken
down into two smaller cycles:
• Instruction cycle
It performs fetching and decoding.
• Execution cycle:
It performs executing and storing.
16. Factors
Affecting
Processing
Speed
There are some factors that affects the
processing speed,as:
Main Memory:
These are small chips on the motherboard
to store programs and data,such as, volatile
memory and non-volatile memory.
Registers:
It controls the instructons to be executed
next.The size of the registers, which is
sometimes called the word size.The bigger
the word size, the more quickly the
computer can process a set of data.
17. Types of
Main Memory
Volatile memory :
• It requires power to hold data ,such
as,Random Access Memory (RAM) .
Nonvolatile memory:
It holds data when power is off ,such
as,Read-Only-Memory (ROM) ,Basic
Input Output System (BIOS) ,Power
On Self Test (POST) .
18. More RAM
Makes
Computer to
Run More
Fast
Virtual memory:
• It is space on the computer storage
devices(usually on the hard disk drive) that
stimulates aditional RAM in the computer.
• It moves the data and commands from RAM to
the computer storage devices and swapping into
the new data and commands to enables the
program to run fast .
• It is,however,slower than RAM.
Chache memory:
• Cache memory is high-speed memory that
holds the most recent data and instructions that
have been loaded by the CPU.
• Cache is located directly on the CPU or
between the CPU and RAM, making it faster
than normal RAM.
19. The Bus
• A bus is an electrical path between the
components of a computer.
Data and instructions travel along these
paths.
20. Types of Bus
• Data Bus:
The data bus width determines how many
bits can be transmitted between the CPU
and other devices.
•Address bus:
The address bus runs only between the
CPU and RAM and carries nothing but
memory addresses for the CPU to use.
•Expansion bus:
Peripheral devices are connected to the CPU
by an expansion bus.
•Universal Serial Bus (USB):
Universal Serial Bus (USB) enables many
devices to be connected to one port.
•Small Computer System Interface (SCSI):
Small Computer System Interface (SCSI) is
an older standard for extending the bus to
multiple devices through a single port.