SheepShaver: Open-Source PowerPC Mac Emulator

SheepShaver is an open-source PowerPC Apple Macintosh emulator capable of running Mac OS 7.5.2 through 9.0.4. Originally a commercial product for BeOS (1998), it was open-sourced in 2002 and ported to Windows, Linux, and macOS. While primary development ceased in 2008, community contributions continue, making it a valuable tool for running older Mac OS versions, especially as the Classic Environment is absent in newer macOS releases. Users need to supply their own ROM image and Mac OS copy.