*ACL* or _Access Control List_ is a security term used to describe a scheme for privilege control depending on user identity and group affiliation.

List refers to a list of security registers, defining a set of rights on objects, typically files on a file system. In that case, each entry would define a matrix of privileges, depending on whether a user was anonymous, the owner, or the group owner of a file, and whether the file permitted execution, reading, or writing.