These are what i usually call the different kinds of jumps you can get in tux.

Jumping onto enemies can have different out comes depending on how you control the jump button.

Neutral - Jumping on an enemy, letting go as you peak, such that you get a mediocre 2.5-ish tile bounce. This is like tapping space onto an enemy basically. Locked High - Jumping, letting go at some point during the jump, and holding space before you land on the enemy. This locks your upwards momentum. This is useful in rare, tight cases where you don't have enough horizontal space to have a variable jump. Variable - Jumping, continually holding space as you land onto the enemy, and being able to let go at any height you wish after landing on an enemy. This one is incredibly useful for some scenarios, and also still counts if you hit your head on a ceiling. Sometimes you can cancel the jump immediately (or even slightly before, if you're good) and tux will do a very small jump, under 2-ish tiles. This resulting jump is called a "low-bounce" and it gives a smaller downwards momentum than a neutral. 1-frames - Simply tapping the jump button for a singular frame. Tux will jump under 2 tiles high. 0-frames - Pressing jump and pause on the same frame gives tux 1px of height. This isn't really too useful mainly because its unexplored but it might have some future use in investigating Yeti boss fights in TAS. Variable Start - 0.5.1 and lower Only. When starting a level, tux can jump on the first frame after the black screen. This type of jump is variable and tux can cancel his jump at any stage. This can be seen here:

Boosting and small tricks

Whenever you jump on an enemy, there are two points of the enemy that can push you backwards or forwards a few frames. I personally call this a displacement, but its more common now to call it a boost considering you can almost see the visual effect of this trick. I found that this possible to also do against solid hitboxes, back when I started running this game.

There are also types of jumps called ICGs, or Instant ice cube grabs, (portmanteau is ICG) which relies on tux jumping into a specific area of an ice cube and holding action. This usually means they're frame perfect. ICGs are trajectory-achieved in that if you have more downwards momentum it seems to be more common to ICG. sometimes ICGs are impossible due to how pixels align.

Hyperspeed occurs when tux throws an owl's skydive behind him and re-grabs it a few frames later, running forward for a few frames, and then throwing it behind him again to glitch it, and then grabbing it for a single frame before continuing to run forward. This then glitches the skydive from left to right and boosts tux forward. It was described as boosting tux each frame, but the pixel distance a skydive gives each frame is more than a maximum boost (12px, or 2.4F).

There is also a lesser known trick where you can jump into the hitbox of a snowman in such a way it kills both stages of it. I've done this once with an air flower and never reproduced it. This is called an "instant snowman stomp" or ISS for short.

Sometimes boosts are impossible as demonstrated by my TAS here: where at the beginning, it is impossible to frame boost off the bonus block immediately. This is due to pixel alignments. If you've ever seen MK64 runs and have heard of "0-framed" this applies here. There is sometimes no frames where tux is able to boost because he is either too far behind, or ahead, on each consecutive frame of the attempt such that he cant position his hitbox in a way to nudge him forward.

Play around with these kinds of jumps. Look at ILs and see how people use them. They're very useful when pushing the game for more optimal times, since you don't have to slow down as much to avoid awkwardness with enemies.

Happy Tuxing!