store and process information.
Computers help you perform a variety of tasks such as:
• Receiving and sending messages to family and
friends,
• Making presentations, and maintaining records.
Computers are also used in:
• education
• research
• broadcasting news
• making weather forecasts
• Other business and recreational activities
You can save time, effort, and money by using computers.
A system is a set of interrelated elements which must come together to achieve a common goal.
A computer system is a collection of devices that function together to process data.
Information System. System of hardware, software, data, people, and procedures that allows a
person to obtain useful and timely information from a computer.
Hardware is the electric, electronic, and mechanical equipment that makes up a
computer. The physical components.
Software is the series of instructions that tells the hardware
how to perform tasks. Without software, hardware is useless; hardware needs the
instructions provided by software to process data into information. Programs and
applications.
Data is a collection of raw unprocessed facts, figures and symbols.
Peopleware includes the users who communicate with a computer or use
the information it generates or developers, who design hardware or write
software.
Procedure is an instruction, or set of instructions, a
user follows to accomplish an activity.
1.1.1. THE ROLE OF COMPUTERS
Computers play a major role in our daily lives. They are used in various places, such as:
• Industries
• schools
• government offices
• shops
1.3.2 OUTPUT DEVICES
An output device is used to convey the information generated by a computer to a user.
Some examples of output devices are described in the following list:
• Monitor: A device that is similar to a television.
�� It is used to display information in visual form, using text and
graphics.
• Printer: A device that you use to transfer text and images from a
computer to a paper or to another medium, such as a transparency film.
�� You can use a printer to create a paper copy of whatever you see on
your monitor.
• Speaker/Headphone: A device that allows you
to hear sounds. Speakers may either be
external or built into the computer.
1.3.3 SYSTEMS UNIT
The system unit is a box-like case made from metal or plastic that houses the computer electronic
circuitry. The circuitry in the system unit usually is part of or is connected to a circuit board called
the motherboard.
The video card, sound card, IDE hard drive, etc. all plug into the motherboards various slots and
connectors. The CPU also plugs into the motherboard via a Socket or a Slot.
Two main components on the motherboard are:
1. Central Processing Unit (CPU)
The central processing unit (CPU) is the heart and brain of the
computer. It is a device that interprets and runs the commands that
you give to a computer. It is the control unit of a computer. The CPU
is also referred to as the processor.
The CPU contains the control unit and the
arithmetic/logic unit.
• Control Unit directs and coordinates
most of the operations in the
computer.
• Arithmetic/logic unit performs the
arithmetic, comparison, and logical
operations.
Most of the devices connected to the computer
communicate with the CPU in order to carry out a task.
The arrows in this figure represent the flow of data,
instruction, and information.
