ROM - Read-Only-Memory: a memeory unit in which data is stored permanantly, and cannot be changed or erased (e.g. a compact disc also known as a CD-ROM).

SENSOR - are the devices that convert light into electronic data. There are two main types, CCD (charged coupled device) and CMOS (complementary metal oxide semiconductor).  CCD sensors are more expensive but give great fidelity and light sensitivity.  CMOS sensors are cheaper, have less sensitivity and consume less power.  Because digital cameras are often compared to their 35MM film counterparts, digital camera sensitivity is often rated on the film "ISO" standard for film sensitivity. ISO 100, 200, 300, 400 etc.   The higher the number, the greater the sensitivity.

SCAN - Means of putting a print or, slide or negative into the computer. Converting analogue data into digital format.

SCAN RESOLUTION - this is primarily determined by the capability of output device. To work on an image on screen only, the scan resolution will be that of the screen.

SCSI - industry standard socket for connecting peripheral devices such as printers and scanners to computers. This socket is rapidly being taken over by USB and Firewire.

SYQUEST DISC - high density, removable data storage disc which can be used to transfer images from one computer to another.

SYQUEST DRIVE - a device used to 'play and record' SyQuest discs.

THUMBNAIL - a small, low resolution version of an image, used for cataloguing, sorting and finding images.

TIFF - an uncompressed file format that does which produces larger and better quality files than JPEG format. Tiffs will take up more memory space than JPEG format.

USB - Universal Serial Bus. An outgoing connector compatible with virtually all PCs and Apple Macintosh computers made since 2000. USB connections are much quicker and more user-friendly than a serial port, but it is also a more recent innovation not found on older computers.

WYSIWYG - (pronounced wissy-wig) stands for 'What You See Is What You Get' and refers to the relationship between the screen display on on the computer and the final output.