Previously called the "QUAKE 3 Engine" and one of the most successful licensed engines in history, id Tech 3 was the engine used to create games such as Quake II Arena, Return to Castle Wolfenstein and Soldier of Fortune II: Double Helix. id Tech 3 introduced shaders, curved surfaces, 32-bit color, special effects, bleeding-edge networking and super-smooth speedy hardware rendering.

Font4na says

10/10 - Agree Disagree

This is one of the best game engines from all the times
Bringed for one of the best game developers, id software.

Withouth id, withouth their games, where did we will be right now.