Directories [Files]

A directory is the file system component that contains one or more files or directories. The only constraint on the number of files that can be contained in a single directory is the physical size of the disk the directory is located on.

A directory that contains one or more directories is the parent of the contained directory or directories, and each contained directory is a child of the parent directory. The hierarchical structure of directories is referred to as a directory tree.

The NTFS file system implements the logical link between a directory and the files it contains as a directory entry table. When a file is moved into a directory, an entry is created in the table for the moved file and the name of the file is placed in the entry. When a file contained in a directory is deleted, the name and entry corresponding to the deleted file is also deleted from the table. More than one entry for a single file can exist in a directory entry table. If an additional entry is created in the table for a file, that entry is referred to as a hard link to that file. There is no limit to the number of hard links that can be created for a single file.

Directories can also contain junctions and re-parse points.

For more information, see Hard Links and Junctions, Re-parse Points, Directory Management and Directory Management Reference.