Computers Today
Dec 13, 2015
“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)
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