Source : Free On-Line Dictionary of Computing

Commodore 64
     
         (C64) An 8-bit {Commodore Business Machines}
        {personal computer} released around September 1981.
        Prototypes were (apparently) made before Christmas 1980 (and
        shown at some computer fair).
     
        The {CPU} was a {6510} from {MOS Technolgies} (who were a
        wholly owned subsiduary of Commodore at this time(?)).  The
        C64 had 64 {kilobytes} of {RAM} as standard and a 40-column
        text, 320x200 {pixel} display generating {composite video},
        usually connected to a television.
     
        {DMA}-based memory expanders for the C64 (and C128) allowed
        128, 256, and 512 kb of RAM.  Several third party
        manufacturers produce accelerators and RAM expanders for the
        C64 and C128.  (Some, risking a {holy war}, compare this to
        putting a brick on roller-skates).  Such accelerators come in
        speeds up to 20MHz (20 times the original) and RAM expanders
        to 16MB.
     
        The C64's {1541} 5.25 {floppy disk} drive had a {6502}
        processor as a {disk controller}.
     
        See also {Commodore 65}.
     
        ["Assembly language programming with the Commodore 64", Marvin
        L. De Jong].
     
        (1996-06-05)