Source : Free On-Line Dictionary of Computing

Macintosh II
     
         (Mac II) A version of {Apple}'s {Macintosh}
        {personal computer}, released in March 1987, using the
        {Motorola 68020} {CPU}, which runs at a higher {clock rate}
        than the {Motorola 68000} used in the original Mac.  The Mac
        II has a full 32-bit data bus instead of a 16-bit bus.  Mac II
        models have built-in 40 to 160 megabyte {hard disks} and can
        take up to eight megabytes of {RAM} (and more as denser memory
        chips arive).
     
        The Mac II was the first Macintosh to provide a colour
        graphics option, with up to 256 colours on screen at a 640x480
        resolution.  Mac II models are designed for expandability with
        three ({Macintosh IIcx}) or six (II & IIx) built-in {NuBus}
        {expansion slots} for additional {peripheral} and
        {coprocessor} boards.
     
        (1996-05-25)