Bullet Time refers to a digitally enhanced simulation of variable speed (i.e. slow motion, time-lapse…) photography used in films, broadcast advertisements and video games. It is characterized both by its extreme transformation of time (slow enough to show normally imperceptible and un-filmable events, such as flying bullets) and space (by way of the ability of the camera angle—the audience's point-of-view—to move around the scene at a normal speed while events are slowed). The first movie to use the Bullet Time technique was Blade in 1998, where bullets were computer-generated and digitally implemented. However, the actual term Bullet Time is a registered trademark of Warner Bros., the distributor of The Matrix. It was formerly a trademark of 3D Realms, producer of the Max Payne games.

The Bullet Time effect was originally achieved photographically by a set of still cameras surrounding the subject. These arrays are usually triggered at once or sequentially. Singular frames taken from each of the still cameras are then arranged and displayed consecutively to produce an orbiting viewpoint of an action frozen in time or as hyper-slow-motion. This technique suggests the limitless perspectives and variable frame rates possible with a virtual camera. However, if the still array process is done with real cameras, it is often limited to assigned paths.
For many years, it has been possible to use computer vision techniques to capture scenes and render images of novel viewpoints sufficient for Bullet Time type effects. More recently, these have been formalized into what is becoming known as free viewpoint television (FTV). At the time of The Matrix, FTV was not a fully mature technology. FTV is effectively the live action version of Bullet Time, without the slow motion.
In The Matrix, the camera path was pre-designed using computer-generated visualizations as a guide. Cameras were arranged, behind a green or blue screen, on a track and aligned through a laser targeting system, forming a complex curve through space. The cameras were then triggered at extremely close intervals, so the action continued to unfold, in extreme slow-motion, while the viewpoint moved. Additionally, the individual frames were scanned for computer processing. Using sophisticated interpolation software, extra frames could be inserted to slow down the action further and improve the fluidity of the movement (especially the frame rate of the images); frames could also be dropped to speed up the action. This approach provides greater flexibility than a purely photographic one. The same effect can also be produced using pure CGI, motion capture and universal capture. It is thought that the opening sequence from the late 1960s Speed Racer cartoons partially inspired the Wachowski Brothers to incorporate the Bullet Time effect into The Matrix.