Here you find explanation for computer terms.

Our dictionary is sorted alphabetically so you can easily find the words you are looking for.




Handheld
Please read PDA.


Hard Disk
The hard disk is an internal data carrier of the computer. They differ in the size of case, there are 2,5" (mainly for notebooks) and 3,5" hard disks available. Hard disks consist of thin magnetic discs which are written by a writing/reading head. Depending on the information (binary data has only two values: one or zero), the magnetic particles are polarised in one or the other direction.


Hard Drive
Please read hard disk.


Hardware Dongle
A small plug which contains a coding system for certain software. IF it is not installed, the program does not run. Elaborate copy protection is therefore almost only used in very expensive products.


Hardware
Hardware is the notion for all fixed components of the computer: Processor, memory chips, graphic, sound and modem cards...


HBCI
Home Banking Computer Interface, security technology for online banking. It enables secure communication between online banking software of the client and internet access of the bank. This works via a special method with chip card or password.


HDTV
High Definition Television. Standard for high resolution digital television.


Headcrash
A headcrash is the hit of the writing/reading head of the hard disk on the surface. Consequently, the drive is damaged and data is lost. Headcrashs occur due to electrical power outages if the disk is not able to relocate its reading heads into the initial position.


Header
The first byte of a file are considered as head oder header. In this part, information about the data type or the file's size are located.


Hertz
The number of Hertz is the unit of measurement of the processor's speed: The vibration of the processor - quarzes per second are indicated in megahertz (Mhz).


HFS
Hierarchical File System used by Macintosh is able to be organised into folders and subfolders. The structure corresponds to the directory tree which is also known by DOS users.


High Color
Umbrella term for the display of 65536 colours. This matches a colour depth of 16 bit.


High Key
High-key photos are a bit overexposed on purpose. This way it becomes brighter and softer, shadows become less intense. Opposite: Low-key.


History
A list, created automatically by the browser and saved in a file on the hard disk. All visited webpages are recorded here and enable for example offline operation within the Microsoft Internet Explorer.


Host
Main computer in a network which controls and supervises the entire network as well as the other computers. Not all networks posess a host. All computers have equal rights in a client-server system for example.


HSB
Colour scheme based on the parameters colour tone (hue), saturation and brightness.


HTML
Hyper Text Markup Language, the language webpages are coded with. It is actually ASCII text and HTML commands are inserted. The webbrowser reconverts the commands and generated the internet page. HTML commands are separated with < and > from the remaining text. The W3C Consortium determines HTML commands as standard. Additionally, there are further developments from producers of browsers, partially differing from W3C standards. If you want to program your own webpage, we recommend the webmaster area with tips, software and interesting links.


HTTP
Hypertext Transfer Protocol, the protocol for the transfer of internet pages.


HTTPD
Hypertext Transfer Protocol Demon, server program which provides HTTP services.


Hub
The hub serves as a connection between different computers in a network. It works slower than a switch, because a collision arises when two data packages from two computers arrive at the same time and the hub is not able to manage both packages simultaneously.


Hybrid CD
CD-ROMs for Windows and Macintosh, containing an ISO-9660 file system according to the conventions of MS-DOS, as well as an Apple file system according to the HFS guidelines by Apple.


Hypertext Documents
Text with links to other parts of the text by means of keywords. At the push of the buttom these breaks can be called up. This is reasonable for the design of electronic instruction manuals in order to activate subchapters in a contextual sensitive way.


Hypertext
Notion from the computer scientist Theodore L. Nelson in the 60's for text which is structured in a three-dimensional way and links from one part of the text to an arbitrary number of other parts. This offers the possibility to read text not only linear but also in a spacial structure.