Hacking Unauthorised access to networked and standalone computers via communication channels.
Half-duplex A transmission system that allows data to be transmitted in one direction at a time along a communication channel.
Hard disk A sealed disk unit which records data on a set of disks within the computer.
hardware The name given to the physical parts of the computer such as the CPU, the memory, storage devices, and input and output devices.
Hashing Retrieving records from direct access media.
Hexadecimal number system A base 16 system comprising of the hex (base 6) and the decimal (base 10).
Hot spot A public area offering Internet access over a wireless LAN home page The main web page available for access at a www. site. It is intended to greet visitors, provide information about the site and direct them via hyperlinks to other web pages with more information.
Home page The file available for access at a web site intended chiefly to greet visitors, provide information about the site, and direct them to other sites with related information.
HTML Hyper Text Markup Language. A markup language used to structure text and multimedia documents used extensively on the World Wide Web.
HTTP Hyper Text Transfer Protocol. A protocol used to request and transmit files, especially Web pages and Web page components, over the Internet or other computer network.
Hub The device to which each computer in a star network is connected.