The DVI [Digital Visual Interface] is a standard for high-speed, high-resolution digital displays.
Below is a 24 Pin DVI Female connector seen at the Computer. The connector diagram and pin-out table show a DVI-I Digital and Analog [RGB]; 29 pins [modified D style] connector. A DVI-D Digital only connector with 24 pins [modified D style] looks about the same with out the 4 analog 'C' pins.

The DVI interface is found on a number of devices including TVs, Computers, Monitors, and Video cards.
Digital Visual Interface was developed by the Digital Display Working Group (DDWG).
Note that the Digital Display Working Group disbanded around 2006, so don't expect an up-grade for DVI.

Digital Video Broadcasting/Digital Audio-Visual Council (DVB/DAVIC),
developed by DAVIC [inactive] and DVB [dvb.org].
Adopted by European Telecommunication Standards Institute (ETSI) and
International Telecommunication Union (ITU)

The pinout table above provides the pin out for a DVI-I connector, supporting both digital and analog signals. Single Link DVI uses 12 of the available pins providing a maximum bandwidth of 165MHz. Single Link connectors do not use pins 4, 5, 12, 13, 20 and 21. Dual link DVI is implemented when all 24 pins are used providing 2 x 165MHz bandwidth. The analog signal are implemented by the 'micro-cross' pins; C1 - C5.
The DDC interface pins use the I2C interface bus, as DDC Data for SDA, and DDC Clock as SCL.
TMDS; Transition Minimized Differential Signaling

The DVI-I connector may be used with a VGA connector by way of an adapter, while the DVI-D [Digital only] is not compatible.

An Apple computer may have either a DVI connector as described above or a Apple display connector [ADC] which is an Apple proprietary interface connector.
Of course you would need to check the latest offering to determine the current video output.
As of 2010 the desired video output would be DisplayPort.

A related article covers Computer Interfaces.