A Stage is the area where battles are fought in the Street Fighter series. Every character in their respective stage has their own unique stage as well as a theme to accommodate it. The character's stage is based off their country; for example, Chun-Li's stage in Street Fighter II is on a Chinese street, with cyclists and markets, and her Street Fighter Alpha stage is on the Wall of China. Stages typically have two invisible walls at the left and right side to keep fighting centered in the area.
Stages do not affect gameplay at all; they are merely for show. However at the end of a fight stages tend to become more active, to cheer the fight. Some stages have the background features come alive in a cartoonish and humorous way; for example, E. Honda's Street Fighter II stage has the painting of the man in the background move, showing a ticket, and the sun painting flashing. Most others have the background crowd's animation sped up repeatedly.
The Street Fighter Alpha series had unique innovations in stage design. In Charlie's Street Fighter Alpha stage, the crowd throws money onto the stage itself when a fight ends. In Dhalsim's Street Fighter Alpha 2 stage, his wife can be seen in the background when he is fighting, either cheering him on or turning her face away when he is injured, and cries when he is defeated.
Since Street Fighter IV, stages are no longer associated to particular characters (with the exception of Crumbling Laboratory for Seth at the final battle); while some do have thematic elements linking them to certain characters (such as Small Airfield, a secret airstrip owned by Shadaloo), characters can be fought randomly in any stage. The only exceptions, aside from the final stage, are Rival Battles, which always take place at a determined stage, but even then the opposing character can appear in different stages when playing with another fighter.