Slide smash
Slide smashing, also known as smash dashing or hyphen smashing, is a simple, but useful technique. To do it, simply dash and use an up smash; the player's character will slide to a stop while performing their up smash. All characters can slide Smash.
[edit] Application
The most obvious use for the slide smash is as an alternative to using the character's dash attack, which is generally mediocre to weak in terms of power; many dash attacks also leave the character vulnerable where as the slide smash is generally difficult to punish. Another use is simply as a set-up to an up-smash, which can be used to combo or to KO. Finally, for fast characters such as Sonic, Captain Falcon, and Marth a slide smash covers decent distance (especially characters with low traction), which is useful for approach.
[edit] See Also
DACUS, a very similar technique with the addition of a canceled dash attack.