Directory (Mathematica Import/Export Format)

File system directory hierarchy. Can contain files and subdirectories.

Directory (Built-in Mathematica Symbol)

Directory[] gives the current working directory.

Directories & Directory Operations (Mathematica Guide)

$InitialDirectory (Built-in Mathematica Symbol)

$InitialDirectory gives the initial directory when the current Mathematica session was started.

$InstallationDirectory (Built-in Mathematica Symbol)

$InstallationDirectory gives the top-level directory in which your Mathematica installation resides.

$UserDocumentsDirectory (Built-in Mathematica Symbol)

$UserDocumentsDirectory gives your default "documents" directory.

$RootDirectory (Built-in Mathematica Symbol)

$RootDirectory gives the root directory of your file system.

ResetDirectory (Built-in Mathematica Symbol)

ResetDirectory[] resets the current working directory to its previous value.

$HomeDirectory (Built-in Mathematica Symbol)

$HomeDirectory gives your "home" directory.

ParentDirectory (Built-in Mathematica Symbol)

ParentDirectory[] gives the parent of the current working directory. ParentDirectory["dir"] gives the parent of the directory dir.