Glossary Search: |
|
View Glossary Submit Term |
|
D |
There are 48 entries in the glossary. |
Pages: 1 |
| A Daemon is a program that is always running on a computer and it is responsible for sending actions to devices when it receives input. For example a printer daemon sends information to a printer when someone wants something printing. |
| |
| Dashboard was first introduced with the arrival of the Mac OS X 10.4 Tiger and it is a user interface that enables access to 'widgets' which show many different things such as the time, date and personal information like phone numbers and addresses. There are also collections of widgets that do other thingssuch as allow the user to play games and keep up to date with sports news etc. To view the dashboard you must click the dashboard icon or press F12, to activate the dashboard widgets you simply drag or click them onto the desktop, to deactivate them click the close box. |
| |
| A Database is a structured way of holding data, and this data is usually organised in rows and columns although some more modern databases can contain images and audio/video files. |
| |
| DBMS (Database Management System) is a software system which standardises the storage of data for easy retrieval, cataloging and questioning of data. Examples of DBMSs are Microsoft Access and FileMaker although there are many different versions. As these databases must be able to communicate with each other it is important that you install Open Database Connectivity software to enable connectivity. |
| |
| DDR or Double Data Rate is an up to date version of SDRAM (computer memory) that is twice as fast as it's predecessor. It is also called DDR-SDRAM and due to its efficient performance (it can both send and receive signals in half the time) it is often used in notebook computers. |
| |
| DDR2 (Double Data Rate 2) is a faster, advanced version of DDR memory and like DDR it can send data on the rising and falling edges of the processors clock cycles although it is twice as fast. DDR2 RAM has an improved design to DDR RAM and this gives the DDR2 RAM a larger bandwidth and this allows a greater volume of data to be passed through the RAM chip. |
| |
| A Deadlink is a link to a Web page (or server) that is continually unavailable. They are very common on the Internet but very unprofessional. |
| |
| Debug is the term used to describe the process of getting rid of any 'bugs' in a computer program. When in development these bugs can occur in the programming but before a program can be released to the public they must be debugged so that any problems are eliminated. |
| |
| A Debugger is a program that enables programmers to find bugs in their programs. Debuggers run the program and highlight any codes which are causing the problems so the programmer can alter them. Often they run through the program step by step and provide detailed descriptions of what ahs gone wrong and when. |
| |
| Default is a preset computer program option, for example if you are creating a text document using Netscape Communicator the default text would be 'Times'. The default option in any program is normally the one that a person would choose, but you can customise the program by choosing different options if you like. |
| |
| Defragment, or defragmenting is a method of increasing the performance of your computer by defragmenting the hard disk. |
| |
| The Deguass button on a computer monitor demagnetises the screen and thus improves the colour. Modern monitors don't have the degauss button as they automatically demagnetise themselves. Flat screen monitors don't have this as magnetism doesn't occur in them. |
| |
| Delete in computer terms means get rid or erase. You can delete files, text and whole documents, this is done from text by pressing the delete button when the cursor is behind the text, or you can delete from inside a body of text by highlighting a section then pressing delete. |
| |
| Desktop is the term used to describe your computer's first screen that contains your icons. Many people put frequently used programs and files on their desktop, much like a real desktop so they have easy access to them. |
| |
| Every time a document is printed is published. Desktop Publishing it the term used to describe this act, it also enables images and text to be placed on the same page ready for publishing without the need of large printing presses and cutting and placing of images on sheets of paper. |
| |
| DHCP (Dynamic Host Configuration Protocol) is used by a network server to appoint IP addresses to computers that are networked. Large networks that need setting up are vastly helped by DHCP as it will automatically assign an IP address from a master list to any computer connected to it. |
| |
| DHTML (Dynamic HTML) is a mixture of HTML, a scripting language (such as JavaScript) which is client side and Cascading Style Sheets to create interactive Web sites. |
| |
| Dialog Box is the term used to describe the window that will appear on the screen when dialog with the user needs to occur. These boxes will usually have options to choose from in them such as save or cancel. Once you have selected your option the changes will be saved and the box will disappear. |
| |
| Digital is the term used to describe the 1s and 0s that all data is made up of. As computers are digital machines that use the binary system they will only read on or off, but this is translated into music or video (in the case of CDs and DVDs). |
| |
| To Digitise anything you will turn it from analog to digital. To create a digital file it must be sampled and the higher the sampling rate the better quality the result. A CD for instance will sample at a rate of 44.1kHz which means it samples audio 44,100 times per second. |
| |
| DIMM (Dual In-line Memory Module) is a tiny circuit board holing memory chips. DIMMs are able to transfer a great deal of data at once as the use a 64-bit bus to the memory. |
| |
| Direct3D is a Microsoft developed API that contains a collection of functions and commands used to operate 3D objects. It enables programmers to write much less code and makes managing 3D objects easier. |
| |
| A Directory is a system that is used for storing information such as files rather like an electronic filing system. A subdirectory is a directory that is inside another one. |
| |
| DirectX is used by developers to create software that is normally used in video games and can control sound effects and video playback. This makes a game for instance look a lot more controlled and uniform. |
| |
| DLL (Dynamic Link Library) is a file that has a range of information and functions accessed through a Windows program. Once the program starts links are created to the .dll files that will be needed. If the link is static it will only operate whilst the program runs, if it is dynamic it will run when needed, making the task more efficient. |
| |
| DNS (Domain Name Server) is a storage system that contains domain and host names on a sort of allocated database on the Internet and other networks. Its most crucial function however is appointing IP addresses for every host name and creates a list of each e-mail accepting mail exchange servers for every domain. |
| |
| DNS Records are text that is stored in zone files and used for the translation of domain names to IP addresses. As the information is purely text is of key importance that the correct text is written otherwise mistakes can occur. |
| |
| Domain Name is the name used (which is unique) to define and identify a computer that is on the Internet from the other systems also on the Internet. |
| |
| Dongle has two meanings. The first means a type of security key which is plugged into a USB port on a computer or laptop and allows only the authorised owner of the dongle to use the computer. The second is an Ethernet card adaptor for a laptop. They are sued because an Ethernet cable is usually too big to fit into a network interface card. |
| |
| Doorway Pages fake Web pages that are SEO optimised in order to rank very highly in a search engine, they then trick you into watching another Web page. |
| |
| Dot Pitch is the term used to describe how sharp the picture on a Cathode Ray Tube monitor is. They are organised in millimetres and the finer the picture the lower the number. Most CRT monitors are around .25 - .28 and anything larger would make a fuzzy picture. A dot pitch is different to a pixel as they are smaller and pixels are mapped onto the dots. |
| |
| Double Click means clicking your mouse twice. It usually has to be done in quick succession, although most computers in the System Preference or Mouse Control Panal allow you to lengthen the amount of time needed to double click successfully. By performing a double click you are asking the computer to do something specific such as open a file. |
| |
| Download is the term used when one computer collects any information form another computer. |
| |
| Drag is the term used when you drag an item on your computer screen, you can do this with icons to move them around or you can drag things from one folder to another. Drag is a very useful feature when using Graphical User Interfaces . |
| |
| A computer Driver is a file (which is normally small) that enables a computer to communicate with specific hardware devices. Drivers are in .dll files in Windows based computers. |
| |
| DRM (Digital rights Management) is the term used to describe the systems related to the copyright of electronic media. This helps companies who publish electronic media such as video and audio files monitor who is accessing them and can prevent unauthorised plays. |
| |
| DSL (Digital Subscriber Line) is the term used to describe the technology used to transfer data over a telephone line and connect to the Internet. It is faster than a normal telephone connection which helps transference. |
| |
| DTD (Document Type Definition) is a term used to define the attributes and tags used in XML or HTML documents. |
| |
| DV (Digital Video) is different to analog video as it records in binary (1s and 0s) rather than frame by frame and as a result can be edited on a computer. Digital video camcorders and other such devices can, using a Firewire (IEEE 1394) cable export the footage directly to a computer. An analog to digital converter must be used to transfer analog video to a computer. |
| |
| DVD (Digital Versatile Disc) is an optical disc that is able to store a great deal more information than a CD, this makes large applications and films to be stored on one disk. |
| |
| DVD+R (Digital Versatile Disc Recordable) is a DVD that is able to be recorded on and the single sided discs can store 4.7GB of data and the double-layered can store 8.5GB. DVD+R is not as common as DVD-R but can still be played on the majority of DVD players and DVD-ROM drives. |
| |
| DVD+RW (Digital Versatile Disk Rewritable) is similar to a DVD+R only it can be rerecorded and rewritten on (as long as the disk has had all data removed first) they are only available as a single sided disk but can still hold 4.7GB of data. They are the perfect choice for anyone wishing to make backups of data and they can be written onto using a burner supporting DVD+RWs. |
| |
| DVD-R (Digital Versatile Disc Recordable) is a DVD which can be written or burned onto. They hold 4.7GB of data and can only be recorded onto once. |
| |
| DVD-RAM (Digital Versatile Disc Random Access Memory) are very much like DVD-RW and DVD+RW however they need to be put into a enclosing cartridge before they can be played, but these will not fit into a normal DVD player. |
| |
| DVD-RW (Digital Versatile Disk Rewritable) is very similar to a DVD-R except the data on it can be wiped in order for it to be written on again. DVD-RW area good choice to use to backup data and they are capable of holding 4.7GB, however they are not double sided and in order to write anything to a DVD-RW you must have a burner that supports DVD-RW. |
| |
| DVI (Digital Video Interface) is a term used for the video connection port that will support analog and digital displays. |
| |
| DVR (Digital Video Recorder) is a video recorder that instead of using video cassettes uses a hard drive to record, play back, fast forward etc. DVRs however have one feature that a video recorder does not and that is that it can put live TV on pause and record whatever the current program is in real time. |
| |
| A Dynamic Page is a Web page that is constantly changing or being updated. Many search engines will favour these kind of pages. |
| |
|