NTFS junction point

In computing, an NTFS junction point is a feature of the NTFS file system that provides the ability to create a symbolic link to a directory which then functions as an alias of that directory. This has many benefits over a Windows shell shortcut (.lnk) file, such as allowing access to files within the directory via Windows Explorer, the Command Prompt, etc.

Junction points can only link to directories on a local volume; junction points to remote shares are unsupported.[1]

Junction points are a type of NTFS reparse point; they were introduced with NTFS 3.0, the default file system for Windows 2000 (Windows NT 5.0). The Windows 2000 and Windows XP Resource Kits include a program called linkd to create junction points; Mark Russinovich of Winternals released a tool called junction which provided more complete functionality. Windows NT 6.0 and later operating systems include an mklink command-line utility for creating junction points.

Source: http://en.wikipedia.org/wiki/NTFS_junction_point