* Old Rod: This rod is the first one you get and is available from the start of the game. It can catch the most basic Pokémon, like Magikarp and Goldeen.
* Good Rod: This rod is obtained after you beat the Elite Four and is capable of catching more powerful Pokémon.
It's important to note that there is no "super" rod in Pokémon Diamond.
Do you want to know more about fishing in Pokémon Diamond, like where to get the Good Rod or what Pokémon you can catch with each rod?