The TAS developer has full control over the game's movement, per video frame, to record a sequence of fully precise inputs.
Other tools include save states and branches, rewriting recorded inputs, splicing together best sequences, macros, and scripts to automate gameplay actions.
In a few months, in June 1999, Finnish Esko Koskimaa, Swedish Peo Sjöblom, and Israeli Yonatan Donner opened the first site to share these demos, "Tools-Assisted Speedruns".
In 2003, a video of a Japanese player named Morimoto completing the NES game Super Mario Bros. 3 in 11 minutes and performing stunts started floating around the Internet.
[1] Creating a tool-assisted speedrun is the process of finding the optimal set of inputs to fulfill a given criterion — usually completing a game as fast as possible.
No limits are imposed on the tools used for this search, but the result has to be a set of timed key-presses that, when played back on the actual console, achieves the target criterion.
The current TAS standing at 216 milliseconds (13 frames) was performed by exploiting a small bug with the Famicom and NES hardware in which the CPU makes many extra "read" requests from one of the controller inputs, registering many more button presses than have occurred; the A button is mashed at a rate of 8 kilohertz (8000 times per second), performing the credits warp glitch.