Fuzzy Guarding: "There is some debate in the American community over the definition of Fuzzy Guard. Some think it's the "mash on block" tactic, where you block low, then immediately high then low again in order to avoid any overhead. I always thought fuzzy guard referred to this glitch, so whatever. Anyways, this glitch occurs when you force someone to block something high and then they try to immediately block low. What happens is that for some reason, the game will think you're blocking low, but the guard animation will look like you're blocking high instead. In fact, if you do an overhead (like a greed sever) at this point, it will actually hit them as if they were standing up and doing nothing."
Source
Frame Trap: A tactic in which you use a move that seems to be punishable but is actually advantageous on block, baiting the opponent into being punished when they attempt to retaliate. <via google
Dash Cancel: Go to training mode and pick Kabal. move to fullscreen (farthest away) from your opponent. Press back, front, B to do his Dash Attack. While he's in the animation (i.e. while you're running at your opponent and have a purple trail following you, but before you've hit your opponent) press back and block at the same time. You'll cancel the dash animation and stop immediately. This is dash canceling, and it's usually used to close the distance between you and your opponent extremely quickly.
Block infinite: This is similar to a frame trap, except with a block infinite you have so much advantage from a certain set of attacks that you can do them continuously on a blocking opponent and they will not have any time at all to counter. their only option is to stop blocking and eat a combo, or else they will die from chip damage. There was a new one discovered with raiden recently, search "mk9 raiden block infinite" on youtube and you should find a video showing it.
If you have any other questions feel free to ask here, or ask google like I did for a better worded answer than I could provide