Types of Computers and Computer Storage

Computer TechnologyCreated by M. GuymonPleasant Grove High

Spring 2003Modified by M. Corbett

Fall 2010

Types of Computers

Microcomputer

A personal computer; designed to meet the computer needs of an individual.

Provides access to a wide variety of computing applications, such as word processing, photo editing, e-mail, and internet.

Desktop Microcomputer

A microcomputer that fits on a desk and runs on power from an electrical wall outlet.

The CPU can be housed in either a vertical or a horizontal case.

Has separate components (keyboard, mouse, etc.) that are each plugged into the computer.

Laptop Computer

A portable, compact computer that can run on an electrical wall outlet or a battery unit.

All components (keyboard, mouse, etc.) are in one compact unit.

Usually more expensive than a comparable desktop.

Sometimes called a Notebook.

Workstation

Powerful desktop computer designed for specialized tasks.

Can tackle tasks that require a lot of processing speed.

Often is an ordinary personal computer attached to a LAN (local area network) so that common resources can be shared OR common projects can be worked on.

Supercomputer

A computer that was the fastest in the world at the time it was constructed.

Can tackle tasks that would not be practical for other computers. Typical uses

Breaking codes Modeling weather systems

Mainframe

Large expensive computer capable of simultaneously processing data for hundreds or thousands of users.

Used to store, manage, and process large amounts of data that need to be reliable, secure, and centralized.

Usually housed in a closet sized cabinet.

Server

Purpose is to “serve.” A computer that has the

purpose of supplying its users with data; usually through the use of a LAN (local area network).

Handheld Computer

Also called a PDA (Personal Digital Assistant).

A computer that fits into a pocket, runs on batteries, and is used while holding the unit in your hand.

Typically used as an appointment book, address book, calculator, and notepad.

Can be synchronized with a personal microcomputer as a backup.

Tablet Computer

a portable computer that uses an integral flat panel display screen or touch screen for primary input and primary display

It is the size of a notebook computer

The Ipad is an example of a tablet computer

System unit

Case that holds the power supply, storage devices, and the circuit boards (including the motherboard).

Motherboard

The motherboard is the main circuit board of the computer.

• It includes the Central Processing Unit (CPU) or microprocessor chip, RAM and ROM chips, interface sockets and/or slots, and other input/output (I/O) ports.

Circuits

The path from one component of a computer to another that data uses to travel.

Circuits run between different components on a circuit boardExamples: RAM and the

microprocessor RAM and various storage

devices

Silicon Chip

Silicon is melted sand.

What the circuits are embedded into to keep them together.

Hertz (megahertz or gigahertz)

A measurement used to describe the speed of the system clock.

A megahertz (MHZ) is equal to one million cycles (or pulses) per second.

1.3 gigahertz (GHz) means that the microprocessor’s clock operates at a speed of 1.3 BILLION cycles per second.

Microprocessor Chip

Our computers have the Intel Dual-core processing chip Other generations of

Intel processors were called

80-88 286 386 486 Pentium

Binary Number System

A method for representing letters or numbers using only two digits, 0 and 1. Bit

Each 0 or 1 Byte

8 bits

Also referred to as Binary Code or Base 2

Byte

EXAMPLES

A – 01000001

Z – 01111010

A byte is equal to 8 bits any combination of

8 1s and/or 0s A byte is the amount

of memory it takes to store one character

Memory Measurements

Bit Each 0 or 1

Byte 8 bits

Kilobyte (KB) Approximately 1,000 bytes Exactly 1,024 bytes

Megabyte (MB) Approximately 1 million

bytes Exactly 1,048,576 bytes

Gigabyte (GB) Approximately 1 billion

bytes Terabyte (TB)

Approximately 1 trillion bytes

Secondary Storage

Secondary storage is needed to store data and programs when the computers power is off.

There are currently 3 types of secondary storage Magnetic Storage Optical Storage Flash Storage/Memory

Magnetic Storage

any storage medium in which different patterns of magnetization are used to represent stored bits or bytes of information

Magnetic storage currently come in 3 forms Magnetic Tape Floppy Disks Hard Disks

Optical Storage

A means of recording data as light and dark spots on CD or DVD.

Reading is done through a low-power laser light. Pits

Dark spots Lands

Lighter, non-spotted surface areas

Types of CDs

CD-ROM Cds that can be read but

not written to Examples

Computer games or music cds

CD-R (writeable) Cds that can be written to

once – about 800 MB CD-RW (rewriteable)

Cds that can be rewritten to up to about 100” – about 800 MB

Types of DVDs (Digital Video Disks)

DVD-ROM DVDs that can be read but not written

to Examples

Movies or PC games that you buy DVD-R (writeable)

DVDs that can be rewritten to once – about 4.7 GB

DVD+R DL (writeable) DVDs that can be rewritten to once –

about 8.5 GB DVD-RW (rewriteable)

DVDs that can be rewritten to up to about 100” – about 8.5 GB

Flash Storage

Nonvolatile storage that can be electrically erased and programmed anew and that retains its data without a power supply

Great for digital cameras and cell phones because they retain image data even when batteries go "dead“.

Resources

Parsons, June Jamrich, and Dan Oja. Computer Concepts. Boston: Course Technology - Thompson Learning, 2002.