Teeter canceling, or TCing, is a technique in Super Smash Bros. and Super Smash Bros. Melee that involves canceling any animation into a teeter animation. Any standing technique can then be used out of a teeter.
How to perform
The easiest and most reliable way to TC is to let go of the control stick just short of a platform's edge while dashing. Utilizing a similar mechanic to edge dashing in Brawl, the game recognizes a lack of input from the player (which must reach a certain point for a player to walk off an edge) and keeps the player from falling off the approached edge. However, with proper spacing (dictated by the chosen character's dashing speed and traction), the player's forward momentum should be enough to carry them into the ledge, which forces the teetering animation and negates the dash's ending lag.
Dashing normally causes large lag when changing directions or stopping. However, these overly long animations can be lessened or negated by TCing, and can allow players to change direction at full speed with practically no opportunities for punishment from the opponent.
This technique involves canceling the dash with a teeter and then starting up another dash in the opposite direction. There is no dash stop animation since the first dash is canceled.
Attack out of a dash
Any standing attack can be used out of a teeter. One common use for this property is to run to an edge into a teeter animation and then performing the attack. This technique is useful for edgeguarding.
Since this technique removes lag both from the dashing animation and from aerial attacks (especially special moves performed in the air), it can be used to continue combos.
Taunt animations can be canceled in Smash 64 as well, which can be implemented for mindgames, humour, or dramatic flair.