COMPREHENSIVE LIST OF TERMS ON THE WIKI
Some simple ones:
WHAT DO THE NUMBERS MEAN?
look at a numpad on a keyobard. Each number represents a direction so 6 is right and 8 is straight up. 5 would be neutral (not moving in any direction). 236A would be a street fighter styled fireball motion and pressing the A button.
WHAT'S A FRAME?
a frame is the smallest unit of time in a fighting game. Most fighting games run at 60 frames per second, so instead of using terms like 0.0125 seconds, we just say 1 frame. For example an attack that starts up in 12 frames means it will be active in 0.2 seconds.
WHAT ARE ALL THE ABBREVIATIONS/ LINGO?
read the conventions link. Here are a few common ones:
CH = counter hit
j = while jumping so j.2C = while jumping, press down + C
black beat/ blue beat = a combo that the opponent could have escaped out of if they had teched
hit confirm = a technique of only doing the rest of a combo if the first hit actually hits the opponent. Some of these can be quite hard.
whiff = an attack that completely misses the opponent. Imagine your attack hitting only the air.
cancel = performing a second attack while the first attack is still happening thereby canceling the animation of the first attack. There are very many types of cancels, and they are all used for various things.
link = a combo where you must wait for the first attack to recover completely before doing the second attack. Links typically take some time to do consistently, so keep on practicing!
gatling = revolver action = normal attacks that cancel into one another.
mixup = having the opportunity to attack the opponent in 2 or more ways at once without giving the opponent much time to react (high/low/crossup/throw).
crossup = jumping over the opponent and hitting them just as the opponent's character turns around. This is useful as it's difficult to block and stops the opponent from doing DPs (because their inputs will be reversed when you cross them up).
tiger knee = the act of doing an air attack very low to the ground. Comes from the command for Sagat's Tiger Knee attack in Street Fighter 2. EX: doing Jin's j.236C by pressing 2369C.
chicken block = jumping into the air and blocking rather than standing on teh ground and being forced to guess a high-low mixup.
DP = dragon punch. Refers to attacks whose utility is similar Ryu's dragon punch from street fighter. This does not mean that the motion to perform the move needs to be the same.
SRK = shoryuken = dragon punch
FD = faultless defense = barrier block. A type of blocking where you negate chip damage and increase pushback at the cost of meter.
IB = instant block. Blocking just before an attack strikes you makes you flash white, recover faster, etc.
FC = fatal counter. Blazblue specific mechanic for making all subsequent attacks in a combo deal more hitstun
IK = instant kill. Guilty Gear specific mechanic for instant killing an opponent. Mostly for show.
OCV = one character victory. Used in team battles where one player defeats the entire opposing team.