DIRECTORY o Single level o Two level o Tree structure ·Path name o Concatenated local names with delimiter:(or or \ oAbsolute path name:start with root () o Relative path name:Start with current directory (.) o Notation to move“upward” (..) o Acyclic graph ·Symbolic link ·Hard linkDIRECTORY  Single level  Two level  Tree structure  Path name  Concatenated local names with delimiter: ( . or / or \ )  Absolute path name: start with root (/)  Relative path name: Start with current directory (.)  Notation to move “upward” (..)  Acyclic graph  Symbolic link  Hard link