Quantum torpedo is special anti-Borg torpedo developed by Starfleet. It contains plasma warhead, but presumably use standard photon torpedo casing (DS9 "For the Uniform", "Valiant"). Its shields are white, when opposed to yellow/orange shields of photon torpedo. It is capable of penetrating Borg shields and is presumably more effective against classic shields than photon torpedoes. Also, in DS9 episode "Defiant", quantum torpedoes were used to disable Cardassian warship, with no physical damage to hull being shown.
Gravimetric torpedo is created by outfitting standard photon torpedo with gravimetric charge, and is theoretically capable of forming wormholes via detonating type-6 protostar. It can be used to destroy Omega Molecule.
Designed to be fired into planet's athmosphere; used by Maquis in DS9 episode "For the Uniform", thought it is unknown whether Maquis stole it from Starfleet or purchased it from third party.
While there are other types of torpedoes in existence, none are seen used by 24th century Starfleet, and are therefore irrelevant.
