File permissions control access rights to an individual file, such as a document, image, or program. They determine exactly who (users or groups) can read, write (modify), or execute that specific file. Folder permissions (also called directory permissions), however, govern access to a directory itself and the items it typically contains. They regulate who can list (see) the contents of the folder, add new files/subfolders to it, and traverse (navigate) through it to access items within. Crucially, folder permissions can also influence the access to files and subfolders inside that directory, often through inheritance.

For example, setting "Read-only" on a payroll spreadsheet (file permission) prevents unauthorized editing. Setting "Modify" permission on a departmental project folder (folder permission) allows team members to create, delete, and change files within that folder structure. Operating systems like Windows, macOS, and Linux all use file and folder permissions as fundamental security mechanisms for organizing and protecting data. Common platforms include local file systems and network shared drives.

Key advantages include granular security control: sensitive files can be individually restricted, while folders manage bulk access efficiently. A major limitation involves complexity; inheritance rules (where items inside a folder adopt its permissions) can sometimes lead to unexpected access if not carefully managed. Proper configuration is critical for data security and privacy, preventing unauthorized access or accidental data deletion within structured directory hierarchies.