Types of Computers and Computer Storage Computer Technology

Types of Computers and Computer Storage Computer Technology Created by M. Guymon Pleasant Grove High Spring 2003 Modified by M. Corbett Fall 2010

Types of Computers

Microcomputer n A personal computer; designed to meet the computer needs of an individual. n Provides access to a wide variety of computing applications, such as word processing, photo editing, e-mail, and internet.

Desktop Microcomputer n A microcomputer that fits on a desk and runs on power from an electrical wall outlet. n The CPU can be housed in either a vertical or a horizontal case. n Has separate components (keyboard, mouse, etc. ) that are each plugged into the computer.

Laptop Computer n A portable, compact computer that can run on an electrical wall outlet or a battery unit. n All components (keyboard, mouse, etc. ) are in one compact unit. n Usually more expensive than a comparable desktop. n Sometimes called a Notebook.

Workstation n Powerful desktop computer designed for specialized tasks. n Can tackle tasks that require a lot of processing speed. n 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 n A computer that was the fastest in the world at the time it was constructed. n Can tackle tasks that would not be practical for other computers. n Typical uses n n Breaking codes Modeling weather systems

Mainframe n Large expensive computer capable of simultaneously processing data for hundreds or thousands of users. n Used to store, manage, and process large amounts of data that need to be reliable, secure, and centralized. n Usually housed in a closet sized cabinet.

Server n Purpose is to “serve. ” n A computer that has the purpose of supplying its users with data; usually through the use of a LAN (local area network).

Handheld Computer n Also called a PDA (Personal Digital Assistant). n A computer that fits into a pocket, runs on batteries, and is used while holding the unit in your hand. n Typically used as an appointment book, address book, calculator, and notepad. n Can be synchronized with a personal microcomputer as a backup.

Tablet Computer n a portable computer that uses an integral flat panel display screen or touch screen for primary input and primary display n It is the size of a notebook computer n The Ipad is an example of a tablet computer

System unit n 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 n The path from one component of a computer to another that data uses to travel. n Circuits run between different components on a circuit board Examples: n RAM and the microprocessor n RAM and various storage devices

Silicon Chip n Silicon is melted sand. n What the circuits are embedded into to keep them together.

Hertz (megahertz or gigahertz) n A measurement used to describe the speed of the system clock. n A megahertz (MHZ) is equal to one million cycles (or pulses) per second. n 1. 3 gigahertz (GHz) means that the microprocessor’s clock operates at a speed of 1. 3 BILLION cycles per second.

Microprocessor Chip n Our computers have the Intel Dual-core processing chip n Other generations of Intel processors were called n n n 80 -88 286 386 486 Pentium

Binary Number System n A method for representing letters or numbers using only two digits, 0 and 1. n Bit n n Each 0 or 1 Byte n 8 bits n Also referred to as Binary Code or Base 2

Byte n A byte is equal to 8 bits n any combination of 8 1 s and/or 0 s n A byte is the amount of memory it takes to store one character EXAMPLES A – 01000001 Z – 01111010

Memory Measurements n Bit n Each 0 or 1 n Byte n 8 bits n Kilobyte (KB) n Approximately 1, 000 bytes n Exactly 1, 024 bytes n Megabyte (MB) n Approximately 1 million bytes n Exactly 1, 048, 576 bytes n Gigabyte (GB) n Approximately 1 billion bytes n Terabyte (TB) n Approximately 1 trillion bytes

Secondary Storage n Secondary storage is needed to store data and programs when the computers power is off. n There are currently 3 types of secondary storage Magnetic Storage n Optical Storage n Flash Storage/Memory n

Magnetic Storage n any storage medium in which different patterns of magnetization are used to represent stored bits or bytes of information n Magnetic storage currently come in 3 forms n n n Magnetic Tape Floppy Disks Hard Disks

Optical Storage n A means of recording data as light and dark spots on CD or DVD. n Reading is done through a low -power laser light. n Pits n Dark spots n Lands n Lighter, non-spotted surface areas

Types of CDs n CD-ROM n Cds that can be read but not written to n Examples n Computer games or music cds n CD-R (writeable) n Cds that can be written to once – about 800 MB n CD-RW (rewriteable) n Cds that can be rewritten to up to about 100” – about 800 MB

Types of DVDs (Digital Video Disks) n DVD-ROM DVDs that can be read but not written to n Examples n Movies or PC games that you buy n DVD-R (writeable) n DVDs that can be rewritten to once – about 4. 7 GB n n DVD+R DL (writeable) n DVDs that can be rewritten to once – about 8. 5 GB n DVD-RW (rewriteable) n DVDs that can be rewritten to up to about 100” – about 8. 5 GB

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