That's a very broad question. It can easily be an entire article (or book). I can list the punches/hand techniques as I know them.
* Lead jab - probe defenses, setup
* Lead straight punch - power punch, knockout potential
* Rear cross - power punch with rear hand
* Lead straight to body - basic body blow
* Lead straight to body with half knuckle fist - seperate ribs
* Hook punch - get around defenses and/or part of combo
* Uppercut - same. (Saw Tarver use this to get around Roy Jones guard in their first fight)
* Shovel hook - Inverted body punch
* Palm smash - "Pimp slap" but far more devistating
* Finger jab - Disrupt vision
* Finger spear - Disrupt breathing (or other things)
* Cutting palm - Disrupt blood flow
* Straight blast - Disrupt consciousness.

* Power blast - Straightblast variation. More powerful punches but less centerline control. (At least that's my understanding)
That's off the top of my head. (I may have likely missed something.) Are there any on the list that you aren't familair with? Oh, and I'm not at all posting this as the "final authority". These are just my ideas.
Regards,
John M. Drake