A file system is commonly represented as an inverted tree. Directories branch downward from the root directory in the tree diagram and contain files and subdirectories. Branching creates unique paths through the directory structure to every object in the file system. Files are typically grouped in a special type of file called a directory. Grouping information improves organization, access time, and flexibility.
Directories contain files, subdirectories, or a combination of both.
File A file is a collection of data in a format that can be read from or written to. Executable programs, simple text, software applications, printer definitions, and commands are all stored in files and treated in a uniform fashion by the operating system. Each directory, except for root, has one parent directory and can have one or more child directories. In the Example File System illustration directory B is parent to directory C and directory B is child to root. The path name for each file and directory in the file system consists of the names of every directory that precedes it in the tree structure.