=====unix Keyword 1=====
File Removal 

====Definition====
File removal also known as file deletion is a way of removing a file from a computer's file system.

The reasons for deleting files are

    Freeing the disk space
    Removing duplicate or unnecessary data to avoid confusion
    Making sensitive information unavailable to others

All operating systems include commands for deleting files (rm on Unix, era in CP/M and DR-DOS, del/erase in MS-DOS/PC DOS, DR-DOS, Microsoft Windows etc.). File managers also provide a convenient way of deleting files. Files may be deleted one-by-one, or a whole directory tree may be deleted.

====References====


  * Wikipedia
  * Professor Matthew Haas
  * Mr. Joe Oppenheim



=====unix Keyword 1 Phase 2=====
Variable (environment / local)

====Definition====
**Environment variable** - within the shell, a variable that is stored in the environment.  Because the environment is inherited by all child processes, environment variables can be thought of as global variables.  However, they are not strictly global, because changes made by the child are not propagated back to the parent.
**Local Variable** - A variable that exists only within the scope in which it was created.  For example. within the shell, a variable that is not part of the environment is a local variable.



====References====

  * Harley Hahn's Guide to Unix and Linux
  * Programming Logic and Design
  * Wikipedia