This article is about the paper folder. For file folders in computers, see Directory (file systems)A file folder (US usage) (or folder in British and Australian usage) is a kind of folder that holds loose papers together for organization and protection. File folders usually consist of a sheet of heavy paper stock or other thin, but stiff, material which is folded in half, and are used to keep paper documents. Files may also contain other things like magazine, cased in music cd's, etc.