Function Key
                  /
              __n___
              I    I                   _________
      Main  _ I    I   Floppy disk     I  ___  I
     Storage  I    I  '                I=(___)=I   - Application Software
              I    I I                 I_/  /__I
              I    I I    INPUT        ~~\  \~~~
              (____) I     |             /__/
                II   I___________
                I(___/___________) - User Interface         Debugging Tool
                (__             I                                    \ __
                   I            /                                      II
                    \          / - Central                             II
                     )        /   Processing                           II
         OUTPUT --  I        (       Unit           .-._               II
                    I_________`,                  o_oo'_)              II
                    ~~~~~***&%~                   `._ `._              II
                        ###@^&&&                     `,  \            /__\
       ._____._        &&&%%## - Overflow            //_(_)_/         ~~~~
       I      o)                (I/O error)         ~~
       (_____,-'                                         Mouse

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