Computers Today

“Old” vs “New” Computers

“Old” computers Keyboard? Monitor? Mouse? How did you put information

in? How did you get information

out?

Computers for Specific Purposes

Computers can now be found in our wrist watches, cameras, televisions, DVD players, etc.

Computers monitor everything from fuel efficiency to the comfort of the passengers.

Specific purpose computers can be used for little else other than for what they are designed to accomplish.

General Purpose Computers The kind of machine most people

think of when they hear the term computer.

What makes them so popular is that it can perform a wide variety of tasks.

General-purpose computers can be programmed to perform many different tasks.

System Components The equipment that makes up a

computer is called hardware. Each piece of hardware is involved

in one of four tasks: input, output, processing, or storage

Input and Output All computers interact with

someone or something. In computers, this interaction is

called input (getting information) and output (giving a response)

Sample Input Devices A keyboard A mouse A microphone Internet Connection

Sample Output Devices A monitor A printer Speakers Internet Connections

Processing and Storage At the heart of the computer, the

inputs are processed and stored, and output is created.

This is accomplished using a variety of devices such as microprocessor, RAM, ROM, a bus and disk drives.

Bus A system of wires that connects

RAM, ROM, the microprocessor, and other devices

In most computers, there are not actually individual wires, but lines etched on a circuit board and flat cables connecting devices

RAM An acronym from Random Access

Memory The computer’s primary storage Where currently running programs

and active data are stored When you turn off a computer all

data in RAM is lost

ROM

An acronym for Read-Only Memory A set of memory chips that have data

permanently stored upon them ROM chips store data and programs

necessary to get the computer started

BIOS Basic Input/Output System on a

Windows based computer A whole set of programs in ROM

used to interact with the screen, keyboard, and disks

Macintosh computers have an extensive set of programs, called the Toolbox, stored on ROM chips

Microprocessor Does the computing and controls

everything else that is going on in the computer.

All of the other parts of the computer support the microprocessor.

The Parts of a Microprocessor Clock – controls the speed of a

microprocessor Clock speeds are measured in

megahertz (MHz)

Primary and Secondary Storage

Primary Storage – RAM Data stored in RAM is lost if power

is interrupted Considered volatile storage A relatively fast way to store and

retrieve data

Primary and Secondary Storage

Secondary Storage – more permanent storage

Usually in the form of disks Examples: hard disk, flash drives,

CD’s, memory sticks

Video

Questions?

What is an input device? Examples?

What is an output device? Examples?

What is a storage device? Examples?

What is ROM? What is RAM? What is the clockspeed of a CPU?