•Computer have a limited resources then OS must well allocate all resources and have the method to manage and support all programs in the system.
•Especially, OS which supporting the multi tasks and multi users must avoiding of scramble resources (for example CPU, memory, I/O devices).
•Generally, program read data from files, save files into the folders and also include of creating, deleting, modifying.
•All above functions, users has to know only name of file and the address of file.
•Some OS can set the privacy to access into file or folder.
•File management vocabulary:
•Directory,
•Folder
•Subdirectory
•Parent directory
•Path
•File name
•File extension