Gotta Catch 'Em All!

 In the Pokemon trading card game, one of your goals is to collect each of the cards, similar to your goal of colleting each of the Pokemon in the Game Boy game. But not all Pokemon cards are as easy to catch as others. The Energy cards are the most basic and most common kind of cards. Your Pokemon cards, Evolution cards, and Trainer cards come in the bottom right-hand corner with a circle, common, uncommon cards are marked with a squre, and rare cards are marked with a star. In addition, some rare cards are printed using holographic foil. These "holo" cards are the hardest to catch and collect.

 If you're mostly interested in playing, there are always good cards appearing in all levels of comonality. (Many of the most popular Pokemon - such as Pikachu, Charmander, Squirtle, and Bulbasaur - are common cards.)