Index -> Interface -> Magnify Window -> Collector Information
In the lower right corner of every Stargate TCG card, you'll find information to help you identify its rarity and the set it comes from. The first number tells you which set the card comes from (for example, 1 is SG-1). The letter tells you the rarity of the card (R is rare, U is uncommon, C is common, UR is ultra-rare, and S is a card found only in starter decks.) Last is the number for that card in the set.
Some cards have a D for their rarity, marking a special Digital card only available in the online version of the game. These cards often feature video clips from the Stargate television series. To play them, click the play button on the corner of the card.
Some cards have a P for their rarity, marking a special Promo card separate from (but related to) a normal expansion set. These cards are made available in a variety of ways, such as rewards for high-level tournaments. These cards may go "out-of-print" when a new expansion is released.
Some cards have a T for their rarity, marking a special Tournament card separate from (but related to) a normal expansion set. These cards are typically made available as rewards for high-level tournaments. These cards may go "out-of-print" when a tournament "season" ends.