Intro To Information Technology

• Disk Caching
• Gile Compression
• File Decompression
• Internet Hard Drive
• Optical Disc Drive
• Solid-State Storage

Disk Caching

• is a mechanism for improving the time it takes to read from or write to a hard disk 
• included as part of the hard disk
• can also be a specified portion of random access memory(RAM)
• holds data that has recently been read and, in some cases, adjacent data areas that are likely to be accessed next

File Compression

• also know as Data Compression
• to encode data before sending it to another place
• commonly used when sending a file from one computer to another over a connection that has limited bandwidth
• makes the file smaller and, therefore, the sending of the file is faster

File Decompression

• reverse of  file compression-decoding of compressed data to restore the unique data

Internet Hard Drive

• to access user's computer files such as pictures, documents, music, videos, etc. from any computer, as long as that computer has access to the Internet
• unlike local hard drive, an internet hard drive provides unlimited disk space
• lower risk to loose documents

Optical Disc Drive

• also known as ODD
• uses laser light or electromagnetic waves to read the data from a disc
• used in computers to read software and consumer media distributed in disc form, and to record discs for archival and data exchange

Solid-State Storage

• also known as SSD
• is a data storage device that uses solid-state memory to store data providing access in the same manner of a traditional hard disk drive
• it contains no mechanical parts, everything is done electronically
• data transfer at a much higher speed

• Ergonomic Keyboard
• Ink-Jet Printer
• Laser Printer
• Magnetic-Ink Printer
• Optical-Character Recognition
• Optical-Mark Recognition

Ergonomic Keyboard 

• computer keyboard that separates the keys into two halves shaped like a wide "V"
• some have a fixed layout, while others are movable
• puts less stress on the hands and wrist and winds up being comfortable platform for typing, for most people.
• designed to to relieve sometimes painful conditions, minimize muscle strain and a host of related problems

Ink-Jet Printer
Optical-Character Recognition


Optical-Mark Recognition

• compact audio/video interface for transmitting uncompressed digital data
• connects digital audio/video sources for examples HD DVD player, PlayStation 3 to compatible digital audio devices like video projector and digital TV

Ethernet port is a family of frame-based computer-networking technologies which connects the computer to the internet modem for local are networks (LAN).

Firewire port also known as High Performance Serial Bus (HPSB).

Firewire is :

• allows connetion between a computer to many different types of peripheral devices
• a very high-speed rate of data transfer that will accommodate multimedia applications for example digital camcorder

Parallel port is also known as :

• printer port 
• Centronics port

A Parallel port is :

• socket on a computer used to connect various peripherals
• to send or receive a huge amount of data in a short distance
• allows eight data bits transferring simultaneously

Serial port is :

• A socket on a computer used to connect a modem, or other device especially in data acquisition terminal
• runs at a very slow speeds
• on the back of a PC is a male 9-pin connector
• good for long distance

Universal Serial Bus port also known as USB.

The USB is :

• the most common type of computer port used in today's computers
• used to connect devices like keyboards, mice, game controllers, printers, scanners, digital cameras ect
• faster than older ports, such as serial and parallel ports

Plug and Play is:

• allows to add new components or devices to a system automatically 
• for examples: headphone, microphone, mouse ect
• recognizes the attached peripheral devices then adjust the appropriate internal settings when starting the computer

Network Interface Card also known as NIC.

Netwok Interface Card is :

• a computer circuit board
• a card that is installed in a computer to make connection between it and the network cable
• provide a dedicated, full-time connection to a network

Also called :

• Sound Board
• Audio Adaptor

Sound Card is :

• a plug-in card that records and plays back sound
• provide an input port for a microphone or other sound source
• output ports to speakers and amplifiers

Also known as :

• Video Card
• Video Adapter
• Graphic Adapter

Graphic Card is :

• the plug-in card in a desktop computer
• creates the electronic signals required by the monitor
• an expansion card that allows the computer to send graphical information to a video display device

Flash Memory is :

• a non-volatile computer storage chip that can be electrically erased and reprogrammed.
• primarily used in memory cards, USB flash drives, MP3 players and solid-state drives.
• used for general storage and transfer of data between computers and other digital products.

ROM stands for Read-Only Memory.


ROM is :

• nonvolatile
• computer memory on which data has been prerecorded
• data cannot be removed and can only be read
• retain its contents even when the computer is turned off
• used extensively in calculators and peripheral devices such as laser printer

Cache is :

• to store data locally in order to speed up subsequent retrievals
• Reserved areas of memory in every computer that are used to speed up instruction execution, data retrieval and data updating.
• serve as staging areas, and their contents are constantly changing.
• take advantage that same data item is often reused many times.
• holds copies of recently accessed data such as a web page and pictures on web pages

RAM stands for Random Access Memory.


RAM is :

• small, both in physical size and in the amount of data it can hold.
• any storage location can be accessed directly
• faster to read from and write to than the other kinds of storage in a computer, the hard disk, floppy disk, and CD-ROM.
• data in RAM stays there only as long as your computer is running

• RAM
• Cache
• ROM
• Flash Memory
• Graphic Card
• Sound Card
• Network Interface Card
• Plug and Play
• Universal Serial Bus port (USB)
• Serial port
• Parallel port
• Firewire port
• Ethernet port
• High Definition Multimedia Interface port (HDMI)