TMs and HMs are crucial for teaching your Pokémon new moves:
- Technical Machines (TMs): These are single-use items that teach a specific move to a compatible Pokémon. There are 92 TMs in Diamond and Pearl. They can be found throughout the world, bought in Poké Marts, or received as Gym Leader rewards. Examples include TM01 (Focus Punch), TM13 (Ice Beam), TM26 (Earthquake).
- Hidden Machines (HMs): These are special moves that can be used both in battle and to interact with the environment (e.g., cutting down trees, surfing across water). HMs can be used infinitely and cannot be forgotten by a Pokémon unless you visit the Move Deleter in Canalave City. There are 8 HMs in Diamond and Pearl:
- HM01 Cut: Cuts down small trees.
- HM02 Fly: Instantly travels to previously visited Pokémon Centers.
- HM03 Surf: Travels across water.
- HM04 Strength: Moves large boulders.
- HM05 Defog: Clears fog from battle and the overworld.
- HM06 Rock Smash: Breaks small rocks.
- HM07 Waterfall: Climbs waterfalls.
- HM08 Rock Climb: Climbs rocky ledges.
HMs are essential for progressing through the game, so ensure you have Pokémon in your party that can learn and use them.