A trading card is a small, rectangular piece of cardboard or plastic that features images and information about a specific subject, such as sports players, video game characters, or comic book heroes. These cards are often collected, traded, and sometimes used in games, where players can build decks and compete against each other. Trading cards can vary in rarity and value, with some cards becoming highly sought after by collectors. Many trading card sets are produced by companies like Topps or Panini, and they often include special editions, autographs, or holographic designs that enhance their appeal.