Prodigy Discs have a simple system for choosing the right one: the bigger the number, the more suitable it is for beginners, while 1 and 2 marked discs are good for pros and highly skilled enthusiasts.
Prodigy Ace Line discs are somewhat more affordable but still made for real-world use. A great choice for beginners and for more relaxed playing.
Why are there so many types of discs?
Putters are used not only for putting but also for approaching and sometimes even driving, when you want to make sure the disc won't overshoot. Many putters are made of relatively "sticky" materials to enhance the chance of it being caught by the basket's chains.
Approach and mid range discs see most use on short fairways, and on upshots for longer ones.
Fairway drivers are easier to control than distance drivers and their tendency for skips on landing is a bit smaller.
Hybrid drivers sit firmly between fairway and distance drivers: longer range than fairway drivers, yet easier to control than distance ones.
Distance drivers are suitable for powerful throwers and stiff headwinds. Most beginners are wise to stay away from these discs, as a beginner will only really get the end fade of such fast discs.