'you may see references to ProDOS 1.1, 1.2 1.3, ProDOS 8, and ProDOS 16. ProDOS 1.1-13 Ire version numbers. ProDOS 8 refers to versions of ProDOS that are compatible with Apple IIs using 8bit microprocessors: the IIe, IIc, and the IIGS in 6502-emulation mode.

ProDOS 16 refers to versions of ProDOS that are designed for the 16-bit microprocessor in the Apple IIGS. Applications designed especially for the Apple IIGS will use ProDOS 16. Applications designed for earlier models of the Apple II or for all models of the Apple II family won't.

You can still run DOS 3.3-based applications on the Apple IIGS, but you can't save the documents on 3.5inch disks. DOS 3.3 was designed for 5.25-inch disks with a storage capacity of 143K; 3.5-inch disks have a storage capacity of 800K.

Disk operating systems

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