The Apple IIc is the fourth model in the Apple II series. It was introduced shortly after the launch of the original Macintosh in 1984. The c in the name stands for compact. It is essentially a remarkably compact version of the Apple IIe. The IIc has a built-in floppy disk drive, and was often sold with its matching monitor.
The Apple IIgs is the final model in the Apple II series, equipped with a backwards-compatible 16-bit 65816 CPU. The gs in the name stands for graphics and sound. It is equipped with superior graphics (4096 640x200 in 4 colours, 320x200 in 16 colours, with 4096 colour palette), an high-end Ensoniq 32-voice soundchip, a separate keyboard and mouse, and a Macintosh-like Graphical User Interface.
All machines use a keyboard that cannot communicate multiple simultaneous keypresses, which makes playing games by keyboard difficult. However all generations of machine have analogue and trigger inputs, which are most commonly used for two two-axis analogue joysticks with two buttons, accepted by the majority of games.