A good answer.
Projectiles- Move like weapons, after you send them, you can go onto another technique, they move at a specific path as well.
Streaming- Think of a flamethrower, you must focus and release the stream evenly, unable to perform another technique until you stop the stream. The can be manipulated in movement depending on their size.
Source- Same as both, either can be a projectile or streaming, but a source means you created the technique out a specific place, have a wind spike appear from the ground, a spear of wind appear out of thin air, etc.
Anyway, basic stuff. Wind has a couple interesting forms as well
Dust, the most notable one, can you explain to me what dusty wind might create?