You can create as many tickets you like, at as many different price points as you like. So to set up a discount ticket, e.g. an Early Bird or a Student discount ticket, you can simply use the ticket name and description to make the discount clear and set the price accordingly. You can create fx. two tickets. One called "Normal ticket" at 100USD, and another called "Normal ticket with 25% discount" at 75USD.
Note, that you can also use the ticket restricted acces option to create special discount tickets that should only be available for a selected group.