mountpoint

A mount point is a directory in a computer's file system that serves as the access point to another file system or storage device. When a file system is mounted at a mount point, its contents appear under that directory as part of the same file hierarchy. The operation is reversible: unmounting detaches the file system and the original contents of the mount point become visible again.

In Unix-like operating systems, the file system tree is a single hierarchy. To use a partition, external disk, network volume, or virtual file system, the system mounts it at an existing directory, which becomes the root of the mounted structure for the duration of the mount. A directory used as a mount point is typically empty or reserved for mounting; mounting over a non-empty directory hides its prior contents until unmounted. The current set of mounted file systems is recorded in a mount table, commonly /proc/mounts or /etc/mtab, and configuration for automatic mounting at boot can be defined in /etc/fstab. Common mount points include / (root), /home, and /mnt or /media for removable media. Mount options can constrain access and behavior, such as read-only mode or special filesystem semantics.

In Windows, the concept exists as drive letters and directory-based mount points, where a folder can serve as the access point to another volume. Mount points are managed using tools such as mountvol or Disk Management.

See also: mount, umount, fstab, /proc/mounts.