I've played a lot of
Street Fighter, and all its derivatives, and I've read a lot of material on these games, and, in order to keep it sane, a standard notation has developed.
Variations abound, and sometimes little pictures take the place of the letter combinations for the directions, but it's all
intelligible after you've spent a week at an arcade, a week with a guide, and then another week at an arcade (or even,
shudder if you play at home,
goddamn hermit).
If you happen to come upon an old Street Fighter II machine, and you've got the tablature for a cross-up, six-hit redizzy combo that's full of dp's and fb's, you might just wanna know what the hell the sequence of letters means, for that to happen, you can just keep looking at this.
Okay, the directions look like this.
Down - D
Diagonally Down & Forward - DF
Forward - F
Diagonally Foward & up - UF
Up - U
Diagonally Back and up - UB
Back - B
Diagonally Down and Back - DB
Some people use Toward and Away instead of Forward and Back, so you can substitute Ts for Fs and As for Bs, if your publisher has been so inclined. The button systems of most games, saving the Tekken Series (uses left and right), Mortal Kombat (uses high and low, plus run and block) and Bushido Blade (uses high and low), along with a few others, whose names I don't remember off the top of my head, rely on a heavy/medium/light system of attacks. Some just have heavy/light, and some have certain button combinations to do certain levels of attack (Neo-Geo Fighters are heavily reliant on this, as their four buttons force them to have a double button hit for the heavy attacks), but, barring intervention by innovative styles of game control, notation for attacks usually looks like this:
LP - Light Punch
MP - Medium Punch
HP - Heavy Punch
LK - Light Kick
MK - Medium Kick
HK - Heavy Kick
Also, when looking at move charts,
P - Refers to any punch
K - Refers to any kick
Okay, now that you've taken care of this, and since I'm a Street Fighter Fiend, I'll throw down a few more notes and you can be off. I'd like to introduce you to some basic moves, so you can get up and dance when you're called upon in the arcade.
Fireballs are usually performed with this sequence:
D,DF,F+P
And that '+' means that you press the direction and the button at the same time. Sometimes moves require two buttons to be pressed at the same time, as in Street Fighter Alpha, so D,DF,F,D,DF,F+2P would be Ryu's super special fireball (or Shinkuu-Hadoken), and the '2P' means to press two punch buttons, any two, while if you had to press a certain pair, they'd be designated as 'X+X'. I ahhh... can't think of any moves like that right now, and I'd bow my head in shame, but I'm not nearly through yet. Also, the D,DF,F motion is sometimes referred to as D to F, or QCF (quarter circle forward), because there are a lot of other moves that require quarter circles that aren't forward, or that require half circles or what have you. I prefer the D to F notation to the QC,HC, what-have-you way of doing it, because Sagat's tiger knee would be D to UF+K in that notation, D,DF,F,UF+K in what I'm calling standard, and 3/8CF+K in that method.
Dragon Punches (or their takeoffs, that many many characters have) are done this way:
F,D,DF+P
This move is almost always an attack that'll launch a character off the ground to fend off air attackers, and controller motion for the attack is usually drawn on joystick diagrams as a Z. Other times people will use a Z or a DP (dragon punch) instead of the normal notation for telling you how to do a move. ZF+P (DPF+P) is Ryu's Dragon punch. ZB+K (DPB+K) is Fei Long's Rising Flame kick.
Right now I'm going to slap myself.
Smack!
I was about to try to wrap things up, and I hadn't even mentioned charging yet. As opposed to circular motions and Z motions with the controller, there are characters who have complete repertoires of moves that don't have a single Z or circle in them. They're affectionately (or grudgingly) reffered to as 'charge characters,' and they've got whole lists of moves that have Cs in front of the directions, or the same directional moves in different colors or fonts.
So Guile's Sonic Boom (a charge move fireball) would be:
CB,F+P (or B,F+P)
Armed with this, if you've never touched on the Capcom games, or fighting games in general, and you've no idea how to do moves, then you at least have a starting point.
Good luck and Good night!