SheepShaver is an Open Source PowerPC Mac OS run-time environment. That is, it enables you to run PowerPC Classic Mac OS software on your computer, even if you are using a different operating system. However, you still need a copy of Mac OS and a PowerMac ROM image to use this program. SheepShaver is distributed under the terms of the GNU General Public License (GPL).

Features:

• SheepShaver runs macOS 10.7 through macOS 10.14
• PowerPC G4 emulation on non-PowerPC platforms, direct execution otherwise
• Basic but portable JIT engine (x86, x86_64, mips)
• Copy and paste of text between Mac OS and the host OS
• File exchange with the host OS via a Unix icon on the Mac desktop
• Color video display with support for run-time resolution switching
• Run-time depth switching from 1 bpp to current host depth settings
• Native QuickDraw 2D acceleration for BitBlt and FillRect operations
• CD-quality stereo sound output
• Networking: SheepShaver supports Internet and LAN networking via Ethernet and PPP with all Open Transport compatible MacOS applications

If you are using a PowerPC-based system, applications will run at native speeds (i.e., without any emulation involved). On other systems, SheepShaver provides the first PowerPC G4 emulator, though without MMU, to enable the execution of Mac OS Classic. Performance with the current CPU emulator using basic just-in-time (JIT) translation techniques is roughly 1/8-th of native speeds.

The following platforms are currently supported: Linux (i386, ppc, x86_64), MacOS X (i386, ppc), Darwin, NetBSD 2.0, FreeBSD 5.3 and Windows for x86. Please note that I am pretty careless of the Windows version since I am not a Windows developer. You are heartily invited to join the effort!