A bracket is a tall punctuation mark typically used in matched pairs within text, to set apart or interject other text. Used unqualified, brackets refer to different types of brackets in different parts of the world and in different contexts. The matched pair may be described as opening and closing, or left and right symbols. Brackets include round brackets/parentheses, square brackets, curly brackets/braces, angle brackets, and various other pairs of symbols. In addition to referring to the class of all types of brackets, the unqualified word bracket is most commonly used to refer to a specific type of bracket. In modern American usage this is usually the square bracket and in modern British usage this is usually the parenthesis.