A fishing rod is a tool that the Fisherman job starts off with unstead of a saw. Clicking on water with the fishing rod equiped (The moat will not work) will lead you to a mini game with a picture of a fishing hook going up and down. When the hook turns red click on it and it will give you a panfish a trout and another one. For the fishermen it will take 1/2 of the time it took for any other class.
You can craft one by combining a piece of wood and wool.