Technically this is the backside variation but it’s generally referred to simply as the boardslide. Learn how to boardslide and you’ll have the most basic of all sliding tricks down, and a solid gateway to countless other variations. As with all the fundamentals, it is really important to learn this trick properly. Concentrate on perfecting your technique so that the whole motion feels as fluid as possible and you are confident enough to go fast.
A word of caution though: this trick is easy once you’ve mastered it but it can deal out a mean slam if you stick on the slide so be sensible. Pick something mellow to learn it on like the flat bar featured here; don’t try to take this one straight to the handrails unless you enjoy pain.