Napalm was a type of gel that can be ignited and used as a weapon. I can be used in flame-thrower or in bombs.
The recipe for napalm were present in the databanks on the USS Verdun. In 2163 Commodore Lucian Murat had downloaded the schematics that were used by the Human forces on Torgu-Va to make this weapon in their fight against the Tarn. It was dropped in bombs from the P-51 Mustang. (TNG novel: The Forgotten War)