the components of an information system - introduction
TRANSCRIPT
The components of an Information System -
Introduction
Keyboard Mouse
Speakers
Disk drive
Visual display unit/VDU/MonitorCentral processing unit (CPU)
Hard disk (Backing store)
Microphone
HARDWARE is the term used to describe the parts of a computer that can be touched and handled.
SOFTWARE is the term used to describe the programs that allow the hardware to perform tasks.
HARDWARE is also the term used to describe the devices that make up a computer system.
These are:• Input devices• The central processing unit• Backing storage• Output devices
Central processing unit (CPU)
Backing store
Output devices
Input devices
A simple computer system
Computers are fast. Computers are accurate. Computers can store large amounts
of information in a very cheaply in a small space.
Computers can work 24 hours per day, every day.
Computers can do work that would otherwise be impossible.
A large computer can perform over 1,000,000 (one million) calculations per second.
If given the right input, computers will always produce the right output.
However, if given incorrect inputs a computer will produce incorrect outputs.
This is called GIGO – garbage in, garbage out!
The cost of administering and maintaining a three draw filing cabinet is estimated to be £2,700 per year.
The cost of a CR-ROM that could store the same information electronically is £0.50.
Computers don’t need meal breaks, become ill, have holidays, or go on strike.
Human beings need meal breaks, become ill, have holidays, and can go on strike.
That said, there are some jobs that humans can do that computer can not.
Computers can be used to design aircraft and cars, and then test the designs. This saves time and money.
Computers can be used to model what happens inside volcanoes so that they can be studied. This would be too dangerous for a human to do.
Computers can replace people in certain types of employment.
Computers are not always secure, and confidential information can be misused.
Computers do not always work! Staff need training to use computers.