		Agtek - Glossary of Computing Terms a b c d e f g h i j k l m n o p q r s t u v w x z

	16 bit	Mode in which an operating system or program code runs, also known as real mode. 16 bit operations are not protected from one another, thus a crashed 16 bit application will crash all other running 16 bit programs. DOS and Windows 3.0 are examples of 16 bit operating systems while Windows 95 / 98 /Me are hybrid 16/32 bit operating systems.
	32 bit	Most program code and operating systems run in 32 bit mode which allows more access to memory ( up to 4GB ) and operating system protection from crashes. i.e. when a 32 bit application crashes it will not crash other running programs or the operating system. Windows NT through to Windows XP are 32 bit operating systems although Microsoft have introduced a 64 bit version of Windows XP.
	64 bit	Standard of operating system operation mode mostly used in High end Servers. Microsoft now provides a 64 bit version of Windows XP providing faster performance and support for memory installation up to 128GB.
	Active Directory	Microsoft database containing user, group and computer accounts in a Windows Server domain.
	Active X	Internet Explorer player to display non standard web content.
	ADSL	Asynchronous Digital Subscriber Line - Type of digital data transmission over telephone copper cable. Similar to DSL.
	AMD	Company name for Advanced Micro Devices - manufacturer of computer processor products.
a b c d e f g h i j k l m n o p q r s	Anti Virus Software	Computer program designed to detect and block insertion of computer virus code.
t u v w x z	ATA	Advanced Technology Attachment - main disk interface for PCs more commonly known as IDE.
	Athlon	Brand name of processors designed and manufactured by AMD.
	Backup	Method of providing recovery of data in the event of data loss.
	Bandwidth	Amount of data that can be transmitted through a connection over a given time period.
	Bit	Basic unit of binary notation represented by either a 1 or 0. All units of computer capacity are multiples of bits i.e. 1 byte is 8 bits, 1 kilobyte ( 1kb ) is 1000 bytes, 1 Megabyte (1MB ) is 1,000,000 bytes, 1 Gigabyte ( 1GB ) is 1000,000,000 bytes.
	Broadband	Collective term for "always on" high frequency bandwidth communications where multiple signals are sent and received simultaneously - The term is usually associated with high speed digital data transmission which when compared to "narrowband" analogue modem connections is said to be a broader band. Typically broadband begins at a download speed of 128 Kb/s and service speeds can reach 8Mb/s.
	Browser	See Web Browser.
	BUS	See FSB.
	Byte	8 bits ( see bit ).
	Cache	Collection of data stored elsewhere to their original location for the purpose of quicker access. Web browsers can cache web pages so that if a page is returned to at a later date only the alterations to the original are downloaded, saving time.
a b c d e f g h i j k l m n o p q r s	CD	Compact disc - optical disk capable of storing data and music.
t u v w x z	CD-Writer	Optical disk device capable of writing data and music to CD R and CD RW disks - now largely superseded by use of higher capacity DVD.
	Celeron	Range of Intel budget processors which are based upon Intel's Pentium processors.
	Centrino	Intel technology which helps provide power and temperature improvements for laptop processor and chipsets allowing for improved performance and enhancements such as wireless connectivity.
	Centrino Duo	Intel technology for Laptops based upon Intel's Dual Core Technology which helps provide power and temperature improvements for laptop processor and chipsets allowing for improved performance and enhancements such as wireless connectivity.
	Chat room	Online service whereby connected users can post messages in real time through a browser application.
	Client/Server Network	Network configuration where one ( or several ) computers serve the requirements of many clients through security logon, file and print, or application. When there are more than 10 computers in a network, administrative overhead determines that a Client/Server configuration should be used over a Peer to Peer configuration.
	Clock Speed	Speed per second that a computer processor performs a cycle of functions both internally and when working with other components. Measured in Hertz - Core clock speed measures operations inside the CPU while a slower system bus speed or ( CPU frequency ) measures how fast RAM memory is accessed. egg a 2.8 GHz Pentium 4 processor performs 2.8 billion internal operations a second. When working with a FSB of 800 MHz the CPU frequency is 200 MHz with a clock multiplier of 14. ( 200 MHz x 4 = 800 MHz 200Mhz x 14 = 2800 MHz ).
	Computer	Electronic machine used for handling data according to a list of instructions known as code
	Computer Virus	Self replicating computer program which inserts itself into executable code or documents usually for purpose of data destruction
	Contention Rate	A high speed link to a communications hub may be shared with other users. Contention ratio is the number of people connected at the same time sharing the same amount of bandwidth. Egg a contention rate of 50:1 means 50 users can be using the same connection at the same time.
a b c d e f g h i j k l m n o p q r s	CPU	Central Processing Unit - Electronic brain of a computer which controls all other components
t u v w x z	CRT	Cathode Ray Tube. Monitor which uses streams of electrons fired at high speed onto the inside of a phosphorescent screen. Now largely being replaced by LCD.
	DAT tape	Digital Audio Tape. High speed magnetic tape used for data backup.
	Domain	A domain is a namespace on the internet which translates into a unique binary address known as an IP address. For example the domain name of this site is www.agtek.ie is translated into an IP address of 81.17.248.20 ( which translates into the binary string 01010001.00010001.11111000.00010100 ). This address is unique on the public internet.
	Domain name	A unique internet name such as agtek.ie or microsoft.com. Domain name registration is regulated and managed by ICANN ( Internet Corporation for Assigned Names and Numbers ) and new domain names are registered through domain name registry organisations.
	DOS	Diskless Operating System - precursor to Windows Operating System.
	Dot Matrix Printer	Printer which uses the impact of a print head onto a ribbon to produce characters.
	DSL	Digital Subscriber Line - digital data transmission over copper telephone lines. Because of attenuation where digital signals weaken over distance, DSL can only reach a distance of about 3 miles from a digital telephone exchange.
	Dual core Technology	Intel processor technology which combines two processor cores into one chip. This reduces chip size and increases performance by allowing CPU to operate two functions simultaneously
	DVD	Digital Versatile Disk ( or digital video disk ) high capacity optical disk used for storage of data, audio and video. Data storage capacities of dual sided DVD discs can reach 4.9GB.
	DVD-Writer	Optical disk device capable of writing data to DVD R+ RW+ disks
a b c d e f g h i j k l m n o p q r s	DVI	Digital Visual Interface. Video interface standard which uses digital signal instead of previous VGA analogue signal used in CRT monitors. This gives a faster clearer display.
t u v w x z	E-mail	Transmission of electronic messages form one computer to another.
	Ethernet	Standardised family of frame based technologies which determine the wiring and signalling standards for the physical layer of computer networks
	Exe file	File which when opened, executes or runs a program or script.
	FAT	File Allocation Table. Contains information relating to position of data file chunks on hard disks. A FAT is created when a hard disk is formatted. FAT comes in FAT16 FAT32 and versions. See also NTFS.
	FDD	Floppy Disk Drive - Low capacity data storage on flexible magnetic disks. Now deemed as "Legacy Hardware" and is no longer standard with new computers.
	Firewall	Software or hardware used in keeping out from the internet, unwanted and unauthorised access to private networks and stand-a-lone computers.
	Firewire	FireWire also known as i.Link or IEEE 1394 is a standard of serial bus interface. FireWire 400 can transfer data between devices at 100, 200, or 400 Mega bits per second.
	Form Factor	Layout standard of computer motherboard which includes different types such as AT, ATX, Mini ATX, LPX and mini LPX. Most common form factor for modern PCs is ATX
	FSB	Front Side Bus - Backbone connection between a computer's CPU and other devices such as RAM and hard disk. Data is moved in bit volume between the major components of computer. Data transfer rate is determined by the CPU clock speed and frequency bandwidth of the data bus. For example a 100 MHz system bus
	GHz	Gigahertz - clock speed per second that a computer performs basic functions 1 GHz equals 1,000,000,000 hertz
	GIF	Standard web graphic format enabling art work display, image animation and transparency.
a b c d e f g h i j k l m n o p q r s	Gigabyte	1 billion bytes or 1,000,000,000 bytes ( see bit ).
t u v w x z	Hard Disk Drive	Data Storage device which stores data magnetically on the surface of fast spinning platters or discs. The read/right heads float above the platters and charge microscopic areas of the disk known as bits. The measurements that these components operate at would be likened to a jet plane flying 1 foot above the ground at 500mph.
	HDD	Hard Disk Drive.
	Hosting	see Web Host.
	Hostname	Name by which a network connected device is addressed by.
	Hotmail	Microsoft's Web Mail service.
	HT Technology	Hyper Threading Technology - Intel Patent technology which allows for enhanced Operating systems such as Microsoft Windows XP to use a single physical processor as two logical processors by use of spare CPU capacity
	HTML	Hypertext Markup Language - programming language used in electronic publishing; especially used as source code for web pages
	HTTP	Hypertext Transfer Protocol - method of transport of html pages over the internet.
	HTTPS	Standard protocol for assessed a web file over the internet using SSL a secure Web protocol that encrypts data. Used when connecting to secure sites i.e. user login or online credit card payment.
	IBM based PC	Design hardware architecture of modern day PCs which is descended from the original IBM PC which was first released on August 11 1981. The IBM PC was based on the Intel X86 architecture which was then capable of using interchangeable commodity hardware. The design was in response to Apple's domination at the time of the microcomputer market. Since then there have been two derived types of computer architecture with Apple producing MACs and other manufacturers producing "IBM-Compatible" PCs. The IBM PC led to the development of the Diskless Operating System which has since evolved into the Windows series of operating systems produced by Microsoft.
a b c d e f g h i j k l m n o p q r s	IDE	Integrated Drive Electronics - disk interface system for attaching disc drives to motherboards. Using 40 or 80 pin connectors and cables. Also known as ATA.
t u v w x z	Inkjet Printer	Print device which propels droplets of ink onto paper to produce high quality images.
	Intel	Manufacturer of computer processor products.
	Internet	Is a worldwide connection of computer networks which are publicly accessible through internet service providers .
	Internet Service Provider	Private company which provides access to the connection of worldwide collection of networks to which they have high speed access links.
	IP address	4 Octet decimal internet address e.g. 81.17.248.20 which is translated from a binary address and is used to translate into a user friendly address such as http://www.agtek.ie .
	ISDN	Integrated Digital Services Network - High speed digital subscriber service for connection to the internet. Basic rate ISDN provides a data rate of 128KB/s. Is largely being replaced in areas by DSL broadband.
	ISP	Internet Service Provider.
	Java	Programming language developed by Sun Microsystems used to program applications.
	JavaScript	Scripting computer language used in adding functionality to Web pages. Not related to Java programming language.
	JPEG	Standard web graphic format mainly used for display of photographs.
a b c d e f g h i j k l m n o p q r s	Keyboard	Computer input device.
t u v w x z	Keyword	Tag attribute in a web page used by search engines to index content
	L2 Cache	Level 2 Cache. Memory component of CPU which acts as a buffer for data and allows CPU to access data faster than requesting from main system memory or RAM.
	L3 Cache	Extra to L2 cache ( see L2 Cache ).
	LAN	Local Area Network - a network covering an area of no more than 2km end to end.
	Laser Printer	Print device which uses a 6 stage process to produce high quality prints. Process involves the electrical charging of paper, a laser beam shining on a photoconductive drum to produce characters, the covering of the drum with power ink called toner, the transfer of the toner to the paper then the heat treatment of the paper to fuse the print image.
	LCD	Liquid Crystal Display. Thin display unit based on electronic charges being applied to liquid crystals altering their state and thus their colour. The technology has long been used in the displays of laptops and until the last couple of years has overtaken the CRT monitor as the standard display device for PCs. Important factors to consider when choosing an LCD monitor are resolution, viewable size matrix type contrast ratio and input port type.
	Legacy device	Hardware device that is not Plug and Play compatible and requires manual configuration.
	Legacy systems	Computer hardware which is no longer mainstream because of improved technologies. For example Floppy Disk Drives are now considered "legacy hardware" because of popularity of other methods of data storage such as CD, DVD and USB drives.
	Local Area Network	See LAN.
	MAC OS	Operating system designed by Apple for their range of Mac iMAc and iBook computers. Applications written for MAC are not installable on Windows systems.
a b c d e f g h i j k l m n o p q r s	Malware	Computer software designed to infiltrate computer without the owners consent. Not usually considered as a computer virus and is therefore not detected by anti virus software.
t u v w x z	Megabyte	One Million bytes ( see bits ).
	Meta tag	A HTML tag encoding information about a web page used by Internet Search Engines in indexing.
	Modem	Modulator / Demodulator. Device used for converting digital signal used by computers into and from analogue signal used over public telephone lines or POTS.
	Monitor	Screen display device.
	Motherboard	Also known as System board provides base for all the hardware components of a computers.
	Mouse	Peripheral device used for moving display screen cursor.
	MP3	High quality audio format used on the internet.
	MS-DOS	Microsoft Diskless Operating System - Microsoft's original pc operating system forerunner of Windows versions
	Net	See Internet.
	Network	2 or more computers that are connected for the purpose of data exchange and sharing resources such as printers.
a b c d e f g h i j k l m n o p q r s	NIC	Network Interface Card - Hardware component used to connect a PC or laptop physically to a network either through cable or wireless.
t u v w x z	NTFS	New Technology File System. Microsoft file allocation system for hard disks which provides enhancement over FAT filing systems and includes features such as file compression, encryption and security.
	Operating System	Computer software which controls the hardware functions of a computer by performing tasks such as disk access, memory allocation, input and output control.
	PC	Personal Computer ( see also IBM based pc ).
	PDF	Portable Document Format. A file format created by Adobe which encodes print documents with fonts and navigation elements. Can be viewed using Adobes free Acrobat viewer program.
	Peer Network	Simple network configuration where there is no single controlling computer. Peer Networks can usually connect between two and ten computers. Beyond ten computers, networks usually become unmanageable and a Client/Server configuration would be required.
	Pentium Processor	Processor series and trademark for CPUs manufactured by Intel since 1993. including Pentium Pro, MMX, PII, PIII and Pentium 4.
	Peripherals	Computer components which are external to the computer casing such as scanners and printers.
	PHP	PHP Hypertext Preprocessor. Web pages that include content processed by a web server before being sent to a web browser.
	Pixel	Single display dot on a computer screen. The screen resolution is the number of pixels displayed i.e. 600X800 resolution displays 480,000 pixels.
	Plug and Play	See PnP.
a b c d e f g h i j k l m n o p q r s	PnP	Plug and Play. Hardware device which does not require manual configuration when attached to a computer system running Windows 98 and above.
t u v w x z	POP3	Post Office Protocol version 3. Internet standard of retrieving e-mail from remote servers.
	Popup Message	JavaScript alert message usually used for advertisement purposes with web pages.
	POTS	Plain Old Telephone System - Public analogue telephone system now largely being replaced by Digital.
	Printer	Device used to transfer image to paper or another medium
	Processor	See CPU.
	Proxy Server	A server that sits between a web browser and the internet providing basic security and cache services.
	PSTN	Public Switched Telephone Network used for conventional analogue voice and data communications.
	QuickTime	Multimedia program developed by Apple.
	RAM	Random Access Memory - semiconductor memory which forms the main memory of a computer.
	RAM	Random Access Memory - Otherwise known as main memory is a data storage format where data is stored by electrical charge and can be accessed randomly by the processor. This is opposed to other storage methods such as hard disk, floppy disk or tape where data has to be accessed in order. When power is switched off to RAM the data is erased because there is no longer a charge to support it. RAM usually comes in chip form on boards which fit into appropriate slots in either a PC or a laptop. There are different standards of RAM including SDRAM and RAMBUS for PCs and SODIMMs for notebooks. A computer will only accept one standard of RAM according to it's Motherboard design. Today a computer with less than 500MB of RAM would be considered a slow computer. Today's new applications and software are written to tommorrow's standards of RAM and processor speeds so that there is some future proofing. A RAM upgrade will noticably improve performance on most systems as it frees the CPU from using virtual memory which is the slower backup memory of hard disk.
	SATA	Serial Advanced Technology Attachment - disk interface system which uses faster more compact cabling than standard ATA.
a b c d e f g h i j k l m n o p q r s	Satellite Broadband	High speed internet access using a dish aimed at an orbiting satellite. Satellite broadband allows for fast download speeds but slow upload ( usually 64 Kb/s ). Latency in speeds makes satellite unsuitable for web hosting or video conferencing. Satellite can be also be affected by bad weather conditions.
t u v w x z	Screen resolution	The number of pixels displayed on a computer screen. The higher the resolution number the greater number of pixels, the clearer the picture display. i.e. 600x800 displays 480,000 pixels. 1280x1024 resolution displays 1,310,720 pixels. On the same sized screen the higher resolution packs the pixels closer together thus producing a clearer picture.
	Search Engine	Web service which indexes web sites and provides a search facility for web users. Popular Search engines include Google, MSN, Yahoo, Alta Vista, Lycos, Infoseek, Excite
	Sound Card	Adaptor providing sound recording and playback function in a computer.
	Spyware	Programs designed to monitor user web browsing history and habits for the purpose of displaying unsolicited advertisements.
	System BUS	Carries 4 different signal types through a computer Data, Power, Control, and Access.
	Tape Drive	Form of data backup using magnetic tape. Examples include DAT Travan and 8mm tape drives.
	Thermal Printer	Print device which produces an image by the selective heating of a print heat which is the applied to heat sensitive paper.
	Trojan horse	Program or virus code introduced without users consent usually when other software is installed.
	UPS	Uninterruptible Power Supply. Provides battery power to a computer in the event of a mains power failure. Also used to condition electrical current to protect electronics from electrical spikes and surges.
	URL	Unique Resource Locator - Address string typed when searching for sites or documents on the internet. The URL of this page is http://www.agetk.ie.
	USB	Universal Serial Bus - Standard of serial bus interface for connecting up to 127 computer components and peripherals. Standard USB transmits data at 1.5 Mbits/sec while "Hi-Speed" or USB 2.0 transmits data at 480 Mbits/sec.
a b c d e f g h i j k l m n o p q r s	VGA	Video Graphics Array. Analogue display interface standard used on CRT and some LCD monitors.
t u v w x z	Video Card	Adaptor providing extra memory separate from RAM for the purpose of running intensive graphics such as those required by gaming and 3D CAD applications.
	Video Standards	Define resolution and colour depth for computer graphics display. VGA defined standard graphics at 640x480 in 16 Colours. Today's standards include SXGA which displays 1280x1024 pixel in 16 million. New standards are appearing for widescreen display.
	Virtual Memory	Area of Hard Disk space reserved by an operating system for use when the electronic RAM memory is full. Excess use of virtual memory degrades system performance because hard disk access is much slower than access to RAM and is an indicator that a real memory upgrade is required.
	VOIP	Voice over Internet Protocol is the routing of voice communications over the internet. With a high speed internet access VOIP offers free or reduced cost to standard analogue telephone services.
	VPN	Virtual Private Networking - method of creating secure private network connections using the internet.
	WAN	Wide Area Network. Interconnection of networks over a wide distance area usually through fibre optic, wireless, or VPN.
	WAP	Wireless Access Point - Device for connecting devices into a wireless network and for connecting to a wired network.
	Web Browser	Program used for viewing electronic documents on the internet. Popular program types include Internet Explorer, Netscape, Firefox, Opera, Lynx, Avant and Apple's Safari.
	Web Host	Company that stores web site and mail systems providing high speed bandwidth connectivity and security.
	Web mail	E-mail service accessible through web browser connection.
a b c d e f g h i j k l m n o p q r s	Web site	Set of electronic documents on the world wide web accessible for viewing through a web browser.
t u v w x z	Wi-Fi	Underlying technology of wireless local area networks based on IEEE 802.11b 802.11a and 802.11g standards. Term now used for mobile laptop connection to WAPs ( hot spots ) in public places.
	Windows	Family of Microsoft Operating systems which began with Windows 3.1 in 1983 through Windows 95 and 98, NT4, 2000, XP and will soon be joined by Microsoft Vista in early 2007.
	Wireless Broadband	High speed internet access which uses low frequency radio waves to connect devices.
	Wireless Network	Network connectivity which uses either infrared, microwave or spread spectrum radio technologies.
	Workgroup	Small group of networked computers.
	World Wide Web	The collection of world wide libraries of data and electronic document displays which are stored on computers. Commonly confused with the term "internet" which is the underlying infrastructure which connects all the computer systems together. When you connect your computer to the internet it becomes part of the infrastructure. When you post a web page from your computer it becomes part of the web information space. To access web information you use a URL which translates an address string into a binary computer address. Web site addresses are themselves translations of unique binary number addresses known as IP ( Internet Protocol ) addresses.
	Worm	Self replicating computer code that attaches itself and becomes part of executable code. Usually exploits file transmission capabilities of e-mail to send itself to infect other systems. During peak attacks Such as the Mydoom infection of January 2004 internet bandwidth was considerably and noticeably reduced.
	www	See World Wide Web.
	Xeon	Range of Intel server-class processors produced for multiple processor computers.
a b c d e f g h i j k l m n o p q r s	XML	Extensible Markup Language - variation to html language used in web display.
t u v w x z	ZIP file	File which contains several other files or file which are compressed for the purpose of moving onto disc or moving over networks.