The Voodoo was the first of a series of 3d acceleration cards. It was first introduced by 3dfx in 1996 and was a huge step in three dimensional rendering. Unlike its successors, the first (and some of the second generation) Voodoo cards were plugged into the computer in addition to the normal VGA adaptor. Later cards (Voodoo 3 through 5, some Voodoo 2 cards) were complete 2d and 3d acceleration cards, while the original Voodoo was only capable of rendering 3d effects. This was achieved by routing the output of a 2d (S)VGA card into an input connector on the Voodoo.
Cards under the Voodoo brand were built from 1996 up until the bankruptcy of 3dfx in the early 2000s. They were bought out by their competitor Nvidia. Some techniques still used today by Nvidia, e.g. such as SLI, have their roots here.
Use in Tomb Raider Games
Tomb Raider I and Unfinished Business support the Glide API used by the Voodoo 1 card, and some of the Voodoo 2 cards like the Diamond Monster are also supported when the correct patch is installed. (Additional information can be found at eidosinteractive.co.uk (archive.org))
Newer Voodoo cards were not always compatible to the original Glide API and therefore it might not be possible to use the same Patches.
The Voodoo cards were one of the first 3d-accelleration cards that were available to the public. Even today, these cards are still rather fast if you want to play 3d games on older retro computers.