up (u) | (ub) up left - 7 8 9 - up right (uf) LP MP HP (b) left - 4 5 6 - right (f) LK MK HK (db) down left - 1 2 3 - down right (df) | down (d)
Assuming your character is facing right, you can move forward by pressing forward, and you can move backward by pressing backward. You can neutral jump by pressing up, backwards jump by pressing up back, and forwards jump by pressing up forward. You can crouch by pressing either down, down back, or down forward. There is no dashing or backdashing in this game.
Normal attacks (AKA normals) are done by pressing any of the attack buttons, though which one you get changes depending on what button and what position the joystick is in. Typically, Light Punches and Light Kicks are fast and weak, while Heavy Punches and Heavy Kicks are relatively slow but strong, and Medium Punches and Medium Kicks lie in between them. In addition to your character's normal moves, characters may also have "Command Normals". These moves are done with a specific direction and a specific button, such as Ryu's f+MP (for more information on what "f+MP" means, check out the Notation Page).
As briefly mentioned, normal attacks change depending on the joystick position. Your character's set of normal attacks change depending on if they are standing, crouching, or in the air. Familiarize yourself with your character's normals, for they are all suited for various different situations.
To block an incoming attack, hold whichever direction is backwards on the joystick. If your character is facing right, hold left. If your character is facing left, hold right. You can also block while crouching by combining the input for down and the input for back. If your character is facing right, hold down and left. If your character is facing left, hold down and right. Additionally, you can also block attacks while in the air. You cannot block while performing an attack.
The different types of blocking each block different things. A standing block will block attacks that hit high and mid, but will not block attacks that hit low (such as many characters' crouching LK, MK, and HK attacks). Conversely, a crouching block will block attacks that hit mid and low, but will not block attacks that hit high (such as every jumping normal). Air blocking will block jumping normals and some special moves (usually projectiles).
Additionally, blocking a special move will take off a tiny bit of damage from your life bar, whereas blocking a normal move does not. Throws cannot be blocked.
Every character has a set of special moves, done by inputting a specific series of directions on the joystick followed by the press of an attack button. For example, Ryu's "Hadoken" is done by inputting down, then down forward, then forward, plus any Punch button (AKA qcf+P). The motion input must be done as a fluid motion.
Aside from being unique attacks that differentiate the cast, another thing that makes special moves special is that they can be "cancelled into" from normals. Not every normal is special cancellable, but the ones that are can be cancelled into a special move by inputting the special move's input while striking the opponent with a cancellable normal, whether the normal hit or was blocked. The inputs for each character's special moves vary. For more info on the different motion inputs, see the Notation Page.
Street Fighter Alpha possesses a chain combo system (also known as the Magic Series). It is similar to cancelling a normal into a special move, only this time you're cancelling normals into other normals.
Throws are done by inputting either backwards or forwards plus Medium Punch or Heavy Punch while close to the opponent. Some characters can throw in the air, while others have an additional throw done with Medium or Heavy Kick instead of Medium or Heavy Punch. Throws cannot be blocked. Use them when you want your opponent to stop blocking.
The moment you get thrown, input the throw command to Throw Tech. While this does not cancel the throw outright like in later Street Fighter titles, you will instead take less damage and land on your feet as opposed to being knocked down.
Upon being knocked to the floor, you can input back, then down, then down back plus a Punch button (AKA rdp+P) to perform a Tech Roll right before you hit the ground. This allows you to avoid being knocked down and being subjected to your opponent's wakeup pressure (AKA okizeme). If you are close enough to the opponent when you Tech Roll, you will pass through them. Note that in this game, Tech Roll works on EVERY knockdown, even Throws. For more information on the intricacies of rolling, see the System Mechanics Page.
One of the defining mechanics of the Alpha series, Alpha Counters are done by inputting back, down back, down, plus either a Punch or Kick button (depending on the character) while blocking an attack. They require one bar of meter to perform.