Chapter 1 of 'I.T. for Management' introduces the definition and components of a computer, which consists of hardware (like the CPU, RAM, ROM, and secondary storage devices) and software. It explores various input and output devices, as well as the roles of buses, ports, and power supply in a computer system. The chapter also discusses different types of software, including system and application software, which are essential for managing and utilizing computer resources.

1. I.T. for Management
Chapter 1
What is Computer& how it works

2. What is a Computer &
How it works
What is a computer
A computer is a device
which can process information

3. What does a computer consist of:
• A computer consists of Hardware and Software
• Hardware is the nuts and bolts of the machine
that is the bare electronic circuit
• Software are the instructions given to the
machine which makes it perform the necessary
tasks

4. Components of a Computer

5. Components of a Computer
•The CPU Central processing unit
•Random access Memory (RAM)
•Read Only Memory (ROM)
•Secondary Storage devices
•Hard disk
•Floppy Drive
•CD/DVD Drive
•Pen Drive

6. Components of a Computer
The Input Devices
• Key Board
• Mouse
• Touch Screen
• Scanner
• Track ball

7. Components of a Computer
The Output Devices
Printer
Plotter
Screen/VDU

8. Components of a Computer
•Bus
•Power Supply
• Ports
•Other peripherals Such as Modems etc

9. Basic functions & Characteristics of
hardware components
CPU
•Brain of Computer
•In present day context CPU is Microprocessor
•It can perform Arithmetic,logic & moment of
data within & with other devices

10. Basic functions & Characteristics of
hardware components
CPU is Characteriterized by:
•Word length 8,16,32 bit processor
•Instruction set
•Clock speed expressed in Mega hertz
•Architecture i.e no of storage areas
called registers

11. Basic functions & Characteristics of
hardware components
What to look for in selecting CPU:
•Larger Word length means greater memory
access,greater speed in instructions per sec.
•Larger Instruction set makes CPU more
versatile
•Higher Clock speed results in higher speeds

12. Basic functions & Characteristics of
hardware components
RAM
•Is memory where all transient data ,programs
& status information is kept while computer
is on& executing some task.
•RAM is volatile & its information is lost
once machine is switched off.
•This increases the overall performance of the
computer

13. Basic functions & Characteristics of
hardware components
• Higher the RAM
available,larger the
space available to the
CPU for storing
programmes & data.

14. Basic functions & Characteristics of
hardware components
ROM
•The read only memory is a memory where
all data programs are hard coded into
•ROM is non-volatile & its information is not
lost once machine is switched off
•As soon computer is switched on micro
code stored (burnt) into the chip gets
activated & is loaded into ROM

15. Basic functions & Characteristics of
hardware components
ROM
• Typically,ROM contains
software functions
required for the operation
such as reading/writing to
a disk or sending
information to printer etc.

16. Basic functions & Characteristics of
hardware components
• Secondary Storage Devices
• Since RAM is volatile,there is need for semi
permanent means of storage.
• The secondary storage devices provides the
means of storing,retrieving ,& modifying
information
• Devices such as Hard disk,tapes,floppy drive are
considered as secondary storage devices

17. Secondary Storage Devices
• What to look for secondary devices
• Speed
• Capacity
• Latency
• Portability
• External Vs
internal fittings

18. Input/Output Devices
• Input /output devices enable human beings to
interact with the computer
• Ihe common characteristics are:
– Character set devices are recognized to certain
character set
– Larger the character more versatile would be
device
– Ports-Parallel ports tend to be faster than serial
ports
– Resolution-this refers to the accuracy & fidelity of
the device in recognizing or representing a
specified letter or symbol
– Closer the representation better the resolution for
instance a picture on low resolution would not

19. Input/Output Devices
• Ihe common characteristics
are:……………(continue)
• Portability:
– Input /output devices tend to get moved around
to suit the users convenience,hence they need to
be more portable & plug& play
• Ergonomically:
– Since computer input/output devices are most
visible components they should be good design
look & feel

20. BUS
• Bus is an electrical connector which connects all
the hardware components of a computer
• Their would be atleast a data bus, a instruction
bus & control bus each carrying
data,instruction& control signals respectively.
• Bus is like common highway shared by all all
data traffic moving between various components
of the computer.
……..Cont

21. BUS
• Since CPU has to access memory
frequently,separate bus is provided which is
known as Direct Memory Access(DMA)
• The capacity of bus is indicated by number of
parallel lines of data traffic moving between the
various components
• Thus it could be 16,32or 64bitbus
• Higher the number of bits faster will be data
transfer& greater bandwidth

22. Ports
• Ports are external interfaces of the bus to
enable people to connect external devices
• The keyboard,mouse,pen drive are all
connected to external ports
• Greater the no of ports offer along with the
comp ,greater the no of devices that can
be connected at the same time
……….Cont.

23. Ports
• There are various standards for Ports
• Serial ports are used by mouse
• Parallel ports are for printers
• Pen Devices fit on USB ports
• The wider the variety of ports available
better it is, since we wish to connect many
devices to computer such as for
audio/video

24. Ports
• Ports are the places on the outside of the
computer case where you plug in hardware.
On the inside of the case, they are
connected to expansion cards.
• There are also extra ports to plug in extra
hardware like joysticks, game pads,
scanners, digital cameras and the like.
• The ports are controlled by their expansion
cards which are plugged into the
motherboard and are connected to other
components by cables - long, flat bands that
contain electrical wiring.

25. Power Supply
• The power supply coverts the A.C. power from
mains to D.C. voltage& current levels so that it
can serve different devices
• It is critical that the power supply provide
exactly the right kind of power or the
motherboard will be fried! Be careful when you
are replacing the power supply or motherboard
that they match

26. Power Supply
• Depending on how many devices
connected to computer you need a power
supply with sufficient capacity.
• Capacity of power supply measured in
terms of Kilo Watts or KVA

27. Modem
• A modem is communication device
• It converts digital signals from computer
into waveforms signals suitable for a
telephone & like back to digital signals
• Modems are characteristics by there
speed expressed in terms of bits per
second

28. Modem
Modems of 56kbs are common now a days
However broadband may require different
types of modems

29. A typical computer configuration
• Microprocessor such as Pentium,Celeron,AMD
• OS such as Windows 98,2000,Xp,Linux etc.
• Ram with size 64 ,128 ,265,512 MB
• Disk Drives Hard Soft,ZIP,CD,DVD
• Display Color,Mono chrome
• Battery lithium,Nickel-Cadmium
• Ports Serial Parallel,USB
• Sound Cards,Speakers etc.

30. Software components of computer
• System software
• Utilities
• Language compilers
• Database Management systems
• Networking & communication Software
• Security related software
• Infrastructure management system
• Wide variety of software components

31. Software components of computer
• Application software
• Canned software
• Packed Function software
• Enterprise solutions
• Custom based solutions using language

32. • I.T. for Management
End of Chapter 1