• ROM 0, 1986, first system, 128K ROM, 256K onboard RAM, onboard battery
• ROM 01, 1987, faster GS/OS operations, 128K ROM, 256K onboard RAM, onboard battery
• ROM 3, 1989, improved GS/OS and GS/OS program operation, 256K ROM, 1 MB onboard RAM, different slot capabilities, 3.6V Lithium battery

• Printer port
• Modem port (AppleTalk support)
• Game port (joystick, paddles)
• Disk drive port (5.25" or 800K)
• Analog RGB monitor
• Composite video out
• Internal game connector (onboard)
• 1 x ADB port
• Headphone jack

• The Apple IIgs supported all graphics modes of previous Apple II models and introduced several new ones through a custom Video Graphics Chip (VGC), all of which used a 12-bit palette for a total of 4096 possible colors, though not all 4096 colors could appear onscreen at the same time. The IIgs is officially compatible with the 12" (11.5" viewable) Apple RGB Monitor A2M6014. Other RGB monitors will work but they must support the IIgs analog signal. There were several third party monitors that were compatible with the IIgs, but all of them required a custom cable and ranged in size from 12" to 15". Compatible monitors have a fairly low horizontal sync rate - 15.75KHz.

• 140K 5.25-inch floppy drive or 3.5-inch 800K floppy drive

• Third party hard drives were available. Apple did not provide an internal hard drive or floppy drive.

Comments
The IIgs ("gs" stood for graphics and sound), introduced in September 1986, was a quantum leap ahead of the earlier IIe or IIc form factors. It was the end of the line for the Apple II family of computers. Woz himself contributed to its design and later lent his name to a limited run "Woz Special Edition IIgs." The IIgs had a graphical operating environment with a Finder very similar to the Mac OS Finder. It was a 16-bit computer while the earlier IIe and IIc were 8-bit computers. Apple introduced a 16-bit version of ProDOS as the IIgs' primary disk operating system. The IIgs had a custom digital oscillator sound chip that could produce up to 15 musical "instruments."

Unlike previous Apple II computers, the IIgs had a detached keyboard and mouse attached thru ADB (Apple Desktop Bus), which later found its way to the Macintosh platform. ADB was similar to PS2 used in the IBM compatibles. ADB added quite a bit of functionality to the system and was used to connect the keyboard, mouse, or other peripherals. The IIgs shipped with a powerful BASIC compiler. Previous IIs used an interpreter, primarily because it tasked the system less and was easier to design in the original Apple II firmware. IIgs BASIC provided many more options and command words than the earlier AppleSoft BASIC due in no small part to the increased capabilities of the hardware. The IIgs remained in production until it was quietly retired in December 1992

Additional Apple IIgs Information:

Apple IIgs Print Ads

DOS 3.3 and ProDOS Guide

Free Programs for the Apple II

Vectronic's Apple II Timeline

The Last II: Apple's Amazing IIgs

Apple Brings Computers to the Masses

Vectronic's Apple II Section

Vectronic's Apple IIgs