Colour Lookup Table [Application Feature] - see "Palette".

Default settings [Application Feature] - these normally take effect when you first start a program.

De-interlace [Application Feature] - to remove the interlacing artefacts resulting from video's two- fields-per-frame, this can be done in an image editing application such as Adobe Photoshop®.

Download [Application Feature] - to copy a file from a server or network to your computer.

MacOS [Application Feature] - Apple's Macintosh operating system.

Palette [Application Feature] - the list of colours which are used in a colour image. Palettes may be as restricted e.g. WEB Palette of 217 colours, or as wide as required depending on the final medium being used to display the image.

Printer Driver [Application Feature] - the program which converts the data from an application program into printable output.

Upload [Application Feature] - to move a file from a computer to a server.

Windows [Application Feature] - Microsoft's operating system.

8-bit [Colour] - monitor colour depth. Allows only 256 colours to be displayed simultaneously also called '256 Colours' on the MacOS. Many older computers only have 8-Bit displays that are inadequate to display true colour values on screen.

16-bit [Colour] - monitor colour depth. Allows thousands (approx 32 thousand) of colours to be displayed simultaneously, also called 'Thousands of Colours' on the MacOS. This is still a poor choice to show true colour values on screen.

24-bit [Colour] - monitor colour depth. Allows millions (approx 16 million) of colours to be displayed simultaneously, sometimes referred to as 'true colour' producing images of photographic quality, also called 'Millions of Colours' on the MacOS.

Additive Colours [Colour] - a type of colour model such as RGB used by computer screens that creates all the colours by adding varying amounts of the additive primaries: red, green, and blue. When mixed in correct proportions, the additive primaries produce white.

CMYK [Colour] - a subtractive colour model used in colour-printing systems based around 4- colour ink on offset lithographic presses (Magazines, Newspapers, Brochures etc... ) - cyan (C), magenta (M), yellow (Y) and keystone black (K). Theoretically, 100% of each of C, M, and Y produces black, but in practice black must be added to obtain a pure colour.

Colour [Colour] - our visual perception of wavelengths of light. Light is processed and transmitted to the brain by the eye. The brain then interprets the wavelengths as colour. The basic colours in the visible spectrum are red, orange, yellow, green, blue, indigo, and violet.

Colour Depth [Colour] - possible range of colours that can be used in an image. These are generally Grayscale, 8-bit, 16-bit, and 24-bit. Higher colour depths provide a wider range of colours, but result in larger file sizes for a given image dimension.

Colour Space [Colour] - a mathematical model that describes colours. Common models include RGB, CMYK. Also called "Colour Model".

Gamut [Colour] - the range of possible colours within a given colour space. For example, the gamut of video playback is dramatically more limited than the gamut of the RGB colour space of computer monitors.

Grayscale Image [Colour] - an image that contains a limited number of tones (256) from white to black.

Pantone Matching System [Colour] - A system of solid ink colour mixing matched to swatch-book samples of numbered colours. Pantone Colours are international standards for colour reproduction of printed materials.

Process Colour [Colour] - four colour (CMYK) printing that prints all available colours by separating an image into its components Cyan, Magenta, Yellow, Black. The separations are turned into printing plates that are then superimposed one on top of the other during the printing process.

RGB [Colour] - Red Green Blue. An additive colour space that directly translates to the red, green, and blue phosphors used in computer monitors. Each colour is described by the strength of its red, green, and blue components. The colour space has a very large gamut and can reproduce a very wide range of colours.

Saturation [Colour] - the vividness or purity of a colour. The less gray a colour contains, the more saturated it is.

Subtractive Colours [Colour] - colours that are formed by the absorption or subtraction of frequencies of light. In a subtractive model such as CMYK, a white surface reflects all wavelengths of visible light, while a black surface absorbs them.

True-colour [Colour] - see "24bit" [Colour]

Bitmap or Bit Image Graphic (.bmp) [File Type] - a graphic image composed from a pattern of dots, the position of each dot in the image must be specified as RGB, often used to distinguish images which are pixel based as compared to images which are vector based. A screen grab/shot from your monitor is a .bmp image.

Encapsulated postscript (.eps) [File Type] - a special form of postscript file useful for transferring text and images from one program to another, commonly used by the printing industry.

GIF (.gif) [File Type] - Compuserve Graphics Interchange Format. A bit-mapped graphics file format limited to images up to 256 (8-bit) colours. This format is widely used online and works best with illustrations with areas of flat colour. (JPEG is a better option for photographic images.)

JPEG or JPG (.jpg, .jff, .jtf) [File Type] - Joint Photographic Experts Group. JPEG is a lossy bit- mapped image format widely used for online graphics. JPEG works well for photographic images. (GIF works better for flat colour illustrations)

Kodak Photo CD (.pcd) [File Type] - Photo CD is a format which is easily accessible by both Macintosh and PC, storing up to 100 images. Each image is stored in a range of resolution levels. Standard Resolution gives 5 levels, from thumbnail through to full photo-resolution at 35mm size.

Lossless [File Type] - describes a process in which no information is lost. Saving a file repeatedly with lossless compression will not affect the image quality.

Lossy [File Type] - compression in which information is lost. Saving a file repeatedly with lossy compression will additionally degrade the image quality. This degradation is known as 'generation loss', e.g. JPEG is a lossy file format when repeatedly opened, resaved and closed.

PCX (.pcx) [File Type] - an image file format, developed by Zsoft Inc.

PICT (.pct, .pict) [File Type] - an image file format containing both vector and bitmap images, as well as text, and an alpha-channel. PICT is a common image format on MacOS.

Portable Networks Graphics (.png) [File Type] - an image file format.

Postscript (.ps, .prn, .cps) [File Type] - a page description language used as standard by a great deal of software and by most mid-high end printers.

Sun Raster (.ras) [File Type] - an image file format, developed by Sun Microsystems Inc.

Suffix (Extension) [File Type] - the last part of a file name indicating the file type. Common suffixes are:
Bitmap - .bmp
JPEG - .jpg
Postscript - .ps or .prn
Microsoft PowerPoint - .ppt
Microsoft PowerPoint Template - .pot
QuickTime - .mov
Video for Windows - .avi

Targa (.tga) [File Type] - an image file format, developed by Truevision Inc.

TIFF [File Type] - Tagged Image File Format. Cross-platform files format for storing bit-mapped images.

Vector [File Type] - refers to formats that store graphical information in terms of mathematical equations, describing the objects portrayed. Since these images don't have any pixels, vector images scale perfectly to any size. Adobe Illustrator, Corel Draw, Macromedia Freehand / Flash, use vector formats.

Windows Bitmap [File Type] - (see Bitmap or Bit Image Graphic (.bmp))

Bit [Measurement] - Binary Digit. A bit is a single computer digit (either a "1" or a "0"). Eight bits = 1 Byte, which is approximately a single character of text.

Byte [Measurement] - a computer data unit, which represents a single character for most languages. One Byte is made up of eight bits.

Dpi [Measurement] - dots per inch. This is a measurement of the resolution of output devices, such as laser printers.

KiloByte (KB) [Measurement] - a unit that describes file size. A KiloByte is 1024 Bytes. The term 'KBps' is short for KiloBytes per second, which is a unit of data rate measurement used in multimedia. Not to be confused with 'kbps' (see below). 1KB = 1024Bytes = 8192bits

kilobit (kb) [Measurement] - a kilobit is 1000 bits. The term 'kbps' is short for kilobits per second, which is a unit of data rate measurement used in reference to audio data rates and telecommunications. Not to be confused with KBps (see above). 1000bits = 1kb = 125Bytes i.e. a kilobit is 8 times smaller (or slower referring to data transfer) that a KiloByte. e.g. 56kb modems operate at = 7KBps.

megabyte (mb) [Measurement] - 1,048,576 bytes.

Pixel [Measurement] - a picture element, the smallest displayed unit of a bitmapped image. A typical resolution computer monitor is 800 pixels wide and 600 pixels tall.

Point size [Measurement] - a measure of the height of characters.

Resolution [Measurement] - the measure of a printer or output device's ability to produce finely detailed output - usually measured in dpi.

3:2 Aspect Ratio [Principle] - 35mm slides aspect ratio. 35mm frame size is not the same as the ratio for PowerPoint's "On Screen Show", it is effectively 'narrower' or 'longer'.

4:3 Aspect Ratio [Principle] - a common display aspect ratio. 800x600 is a 4:3 aspect ratio, also the approximate ratio for PowerPoint's "On Screen Show".

Aspect Ratio [Principle] - the ratio between the horizontal and vertical dimension of your monitor display, or for example any other media such as an A4 piece of paper. It is described as an arithmetical ratio, the dimensions of A4 paper for example is 210x297mm, therefore the ratio = 1:1.41. Similarly a common display aspect ratio of 800x600 pixels has a 4:3 aspect ratio.

Contrast [Principle] - the degree of difference between the lightest and darkest part of a picture.

Gamma [Principle] - a curve describing how the mid tones of an image appears (Not to be confused with 'brightness' and 'contrast'). Changing the value of the gamma affects middle tones while the white and black of the image is unaltered. Gamma adjustment is used to compensate for differences between Macintosh (1.8) and Windows (2.2) displays.

Halftones [Principle] - a way of simulating different tones by printing dots of different size and pattern.

Media [Principle] - a) a generic term for elements such as movies, sounds, pictures, etc. b) storage or transmission devices - such as diskettes, CD-R's, Zip™ disks, email, etc.

Metameric (metamerism) [Principle] - colours that are spectrally different (having different wavelengths), but which appear visually identical under specified viewing conditions.

Pixelization [Principle] - when the pixels that make up an image become 'jagged', often the result of over enlargement, or compression artefacts.

FTP [Telecom] - File Transfer Protocol. A common Internet protocol for transferring files between computers. Often used for downloading files, such as patches or software updates.

HTML [Telecom] - HyperText Markup Language. The programming language the World Wide Web uses to display pages, links to other pages, etc.

HTTP [Telecom] - HyperText Transfer Protocol. The most common transfer protocol used on the Web.

Intranet [Telecom] - a large private network environment, often providing data and audio communications and increasingly video-conference facilities.

IP [Telecom] - Internet Protocol. Commonly used protocol for transferring data over the Internet.

ISDN [Telecom] - Integrated Digital Services Networks. A moderately fast connection to the Internet. Theoretical throughput is either approximately 8 KBps or 16 KBps depending on whether using single channel (64kbps) or two channel (128kbps) connections.

ISP [Telecom] - Internet Service Provider. A Company, which provides access to Internet related services, often including connectivity, email accounts, and web hosting.

LAN [Telecom] - Local Area Network. A network that connects computers and peripherals, often within just one building.

TCP/IP [Telecom] - Transfer Control Protocol. A higher level network transfer protocol used widely on the Internet.

WAN [Telecom] - Wide Area Network. A network connecting a large area, normally more than one building, and often across many sites.

WEB [Telecom] - World Wide Web. Hyperlinked, graphical application of the Internet.

Ascender [Typographics] - the vertical part of some lowercase letters such as b, d and h.

Baseline [Typographics] - an imaginary line running along the base of lower case letters.

Bitmapped Character [Typographics] - a character printed from a pattern of dots, the data specifying the dot pattern of each character is represented as a fixed pattern of dots, as opposed to Postscript characters or fonts.

Bullet [Typographics] - special typographic symbols, normally used to mark a list entry in a report for example.

Character set [Typographics] - a specific collection of letters, numbers and symbols, usually used to provide the characters needed in a particular language.

Dingbats [Typographics] - a specialised font that contains special typographic characters.

Font [Typographics] - a collection of characters (numbers, letters and special characters) with a common design, defined on the basis of its typeface, type style and weight.

Fonts [Typographics] - Standard Type 1 Postscript Printer Fonts: Avante Garde, Bookman, Courier, Helvetica, Helvetica Narrow, New Century Schoolbook, Palatino, Symbol, Times, Zapf Chancery, Zapf Dingbats.

Fonts [Typographics] - Macintosh Standard System Fonts (OS9): Apple Chancery, Capitals, Charcoal, Chicago, Courier, Gadget, Geneva, Helvetica, Hoefler Text, Monaco, New York, Palatino, Sand, Skia, Symbol, Techno, Textile, Times [ Additional non-system fonts added with installation include :- Andale Mono, Arial, Arial Black, Comic Sans MS, Courier New, Georgia, Impact, Times New Roman, Trebuchet MS, Verdana, Webdings]

Fonts [Typographics] - Windows Standard System Fonts: Arial, Arial Black, Bookman Old Style, Cartoon, Century Gothic, Comic Sans, Gill Sans, Gill Sans Ultra Bold, Lucida Sans, Impact, News Gothic, Rockwell Bold, Tahoma, Times New Roman, Trebuchet MS, Verdana, Wide Latin

Font Metrics [Typographics] - the set of widths of each character in a font.

Footers [Typographics] - text repeated at the bottom of each page for a whole document.

International Characters [Typographics] - special set of characters used to enable printing in a particular language.

Justification [Typographics] - the alignment of text with margins either left, right or centre justified. Justify [Typographics] - a text block with even left and right margins, otherwise known as fully justified.

Kerning [Typographics] - adjusting the space between individual letters to produce a more pleasing appearance.

Landscape [Typographics] - a description of page orientation. Landscape (or horizontal) as the name suggests, has the longest paper edge running left to right across the screen.

Leading [Typographics] - the amount of space between lines of text.

Margin [Typographics] - the space around the 'content area' of the page or slide.

Orphan [Typographics] - one or more lines of text left at the bottom of a column or a page.

Portrait [Typographics] - a description of page orientation. Portrait (or vertical) as the name suggests, has the longest paper edge running top to bottom, down the screen.

Printable area [Typographics] - the defined area on a slide that can be printed, excluding any margins.

Proportional Spacing [Typographics] - printing in which narrow characters (such as 'i') are given less space than wide ones (such as 'w').

Scalable Fonts [Typographics] - fonts which can be printed in a range of sizes without coarsening their appearance.

Typeface [Typographics] - a particular style of character design in which the characters share in common such features as body shape and line thickness

WYSYWIG [Typographics] (what you see is what you get) - refers to the ability of some programs to provide an 'accurate' screen representation of the text and graphics that will be printed.