TMs are items that teach certain moves to Pokémon. They can be obtained as drops from defeating boss Pokémon or from PokéLoot chests. They are single-use. To have a Pokémon learn a move through the TM, the TM must be right-clicked on the desired Pokémon. If the TM is compatible with the Pokémon, the Pokémon will learn the move and the TM will disappear.
HMs are similar to TMs, teaching certain moves to Pokémon. Unlike in the Pokémon games, HM moves have no out-of-battle effects; Fly and Surf are not required to mount a Pokémon. Due to this, HMs are cannot be used infinitely, being destroyed upon use like TMs, and the moves they teach can be overwritten by other moves normally; they are functionally equivalent to TMs.