Garbage Collection
This refers to a process where dynamically sorted sections of memory are reclaimed while a program runs. The garbage collector usually carries out garbage collection, which is part of the runtime system. However, it is possible to explicitly write code to do garbage collection as well. Automated garbage collection occurs when the level of free memory falls below a certain predetermined threshold.

Gateway
A gateway is a computer or other device that acts as a translator between two completely dissimilar computer systems, although they are slower than bridges or routers.

GIF (Graphic Interchange Format)
Graphics Interchange Format is a popular bitmapped graphics file format developed by CompuServe. It supports 8-bit color (256 colors). It is based on a patented compression technology.

GUI (Graphical User Interface)
A user interface that displays in graphic or pictorial format rather than in text only.

Hardware
Hardware can be defined as IT-related machinery and equipment. This would include physical machines such as personal computers (PC's), storage devices (such as CD's) and cables etc.

Hits
A hit is a request made by a browser to a website that results in the transfer of a file. When a web page is loaded to a browser the browser makes one request for the text of page and one additional request for each object. When an item is sent from a web site, regardless of its media type, it is counted as a hit. This means that a web page containing 10 graphic images has a total hit rate of 11, whereas a page containing just text has a hit rate of one. For this reason, hit rates are not particularly useful in measuring the popularity of a web site.

Home Page
Normally the main/starter Web page by which a site is accessed.

Host
A computer open for access to other computers. A host site is where an ISP provides the location of a website.

Hot Desking
Hot desking, also sometimes called location independent working, occurs where employees do not have their own desks, but are allocated workspace according to their needs. The system is best suited to firms in which staff spend a lot of time out of the office, for example audit accountants or salespeople, so that space doesn't have to be kept permanently allocated for them. This should have the effect of reducing desk space requirements and therefore cutting costs. An evolution of this idea is the hotel; this is a building in which all office space and facilities are reserved by, and allocated to, staff as the need arises - in the same way that guests book into accommodation. Wi-Fi networks will further enhance hot desking, as cabling is not a limiting factor.

Hot Plugging
If you've ever had to switch off your computer before plugging in a new device (think projectors, for example) then you'll appreciate the convenience of Hot Plugging! It involves the ability to add and remove devices to a computer while the computer is running and have the operating system automatically recognise the change. Two external bus standards: Universal Serial Bus (USB) and FireWire support hot plugging.

HRMS (Human Resource Management Systems)
HRMS encompasses applications for handling personnel-related tasks for corporate managers and individual employees.

HTML (Hyper Text Mark-Up Language)
Hyper Text Mark-Up Language is the authoring language used to create documents on the World Wide Web. HTML, or hypertext markup language, allows you to bring together text, images, audio and video so they can be viewed over the web. HTML tags specify the format and organisation of items on a page.

HTML Document
A HTML document is basically a document that can be displayed in a web browser. Websites are made of many HTML documents that are linked together.

HTML Editor
A software program that makes creating a web page nearly as easy as typing a memo using a word processor. Instead of learning HTML commands, users can format web pages using a menu. HTML editing tools support bullets, tables, paragraph alignment, font size, font colour, indenting, and other common formatting features. Many HTML editor packages display the page being edited exactly the same way it will be displayed on the web - a feature called WYSIWYG, or what you see is what you get.

HTTP (Hyper Text Transfer Protocol)
HTTP is the standard protocol used for transferring Web pages across the Internet . It describes how messages are transmitted and formatted.

HTTPS (Secure HyperText Transfer Protocol)
This is a secure means of transferring data over using the HTTP protocol. Typically, HTTP data is sent over TCP/IP port 80, but HTTPS data is sent over port 443. This standard was developed by Netscape for secure transactions, and uses 40-bit encryption. If you are at a secure site, you will notice that there is a closed lock icon on the bottom area of your browser for Navigator or IE. The HTTPS standard supports certificates. A web server operator must get a digital certificate from third party certificate provider that ensures that the web server in question is valid. This certificate gets installed on the web server, and verifies for a period of a year that that server is a proper secure server.

Hub
A Hub is a simple device that allows several computers to tie into a single point and share a connection to the network. Hubs are the central points of connection for segments within a network and act like repeaters so that every segment receives signals sent from any other segment.

Hyperlink
A highlighted word (or graphic) within a hypertext document (Web page). When you click a hyperlink, it will take you to another place within the same page, or to another page or website.

Hyper-Threading
This term describes the technology now available on many PC's that makes a single-processor think it is a dual-processor - squeezing more processing power for your euro! Intel contends that PC's with HT give a 35% better performance that normal PC's. However to get this performance, the operating system and the applications on the PC need to support HT, which is not the case for many users so it's effectiveness is limited for now. However as HT becomes a standard fixture in PC's then it is likely that applications will be built to be HT compatible.

IM (Instant Messenger)
Like the existing live email conversations such as hotmail instant messenger, IM allows live text message conversations. O2 has a deal with AOL to offer IM on its mobiles across Europe. IM is the most popular application on the Internet after email with 220 million users across the world.

Internet
An international network linking computers across telephone lines, ISDN, cable and mobile services.

Internet Architecture Board
A technical advisory group of the Internet Society, whose responsibilities include:

• Oversee the Internet Engineering Task Force (IETF)
  
• Oversee the Internet standards process
  
• Publish and manage Request for Comments (RFCs)
  

Internet Engineering Task Force
The main standards organisation for the Internet. The IETF is a large open international ebusiness-community of network designers, operators, vendors, and researchers concerned with the evolution of the Internet architecture and the smooth operation of the Internet . It is open to any interested individual.

Internet Payment Provider
A company offering merchant account creation and online transaction services.

Internet Telephony
A category of hardware and software that enables people to use the Internet rather than the traditional telephone to transmit voice or fax. In other words, it adds telephone capabilities to a PC. For users who have free or fixed-price Internet access, Internet telephony software essentially provides free telephone calls anywhere in the world.

ISP (Internet Service Provider)
An ISP is a company or organisation that offers Internet access, merchant account creation and online transaction services to customers for a fee. Some ISPs offer hosting of Websites and Website design and promotion services as well.

Internet Society
A non-governmental, non-profit organisation dedicated to maintaining and enhancing the Internet . Through its committees, such as the Internet Advisory Board and the Internet Engineering Task Force, the Internet Society is responsible for developing and approving new Internet standards and protocols.

Intranet
Intranets are websites that can only be accessed within a company through your internal network or LAN. They are protected from the outside world by a combination of hardware and software security. Intranets are a good way of sharing information within the company; enhancing internal communication and enabling better customer care. Intranets commonly hold products and service guides, employee handbooks, company wide memos, phone numbers and email addresses.

IP Address
An IP address is a unique number that is used to identify a particular host connection to a TCP/IP network. Networks using the TCP/IP protocol route messages based on the IP address of the destination.

ISDN (Integrated Services Digital Network)
ISDN is a communications service offering speeds of 64Kbs and 128Kbs via the telephone network.

Java
An object-oriented programming language, developed by SUN that has seen widespread adoption for use on the Internet . Small Java programs can be embedded within a web page, which are referred to as "applets".

Javascript
An object-oriented programming language that allows Java objects to be embedded directly in a web page.

JPEG
A compressed image format used on the Internet .

JIT (Just In Time)
JIT or just-in-time manufacturing describes an approach in which components or products are only manufactured as they are needed, in the exact number needed, and supplied to the point of use at the exact time they are needed.

Key
A string of digits, used in conjunction with an algorithm, which when applied to original data (plain text) transforms the data to encrypted data (cipher text) which cannot be understood unless de-encrypted.

Knowledge and Collaborative Services
This group of services ranges from setting up a company's first Web messaging system to migrating from an existing legacy mail platform, and the myriad of variations in between.

KM (Knowledge Management)
The creation, storage and collaborative sharing of employee information within the business environment. Through sharing and collaboration, an organisation's efficiency, productivity and profitability is enhanced. Supported by Advanced Information Technology tools and methods.

Knowledge Management Consulting
Helps companies understand, analyse, measure, and manage their organisation's intellectual assets effectively to create a real knowledge organisation.

KPI (Key Performance Indicators)
KPI's are business measurements of the success of an enterprise, not measurements of computer system performance.