A Background is a special type of card that provides each PC with three entries: one each for combat, exploration, and interaction scenarios. The exploration entry ensures that a player is always able to attempt to make progress against an Obstacle, while the other two entries typically provide niche abilities that either improve customization or grant flavor based on the theme of the Background.
Each PC below level 6 chooses a Background as part of character creation. Backgrounds cannot be changed later, as they represent the backstory, culture, race and/or bloodline, childhood, and/or young adulthood of the character prior to the start of their adventuring career. Upon reaching level 6, however, the Background is replaced with a Destiny. At this point in a character's career, where they came from is now much less important than where it is they are going.