It can be used to provide virtual hosting of several virtual computers on a single computer. System emulation In this mode QEMU emulates a full computer system, including peripherals. Fast cross-compilation and cross-debugging are the main targets for user-mode emulation. System calls are thunked for endianness and for 32/64 bit mismatches. QEMU has multiple operating modes: User-mode emulation In this mode QEMU runs single Linux or Darwin/ macOS programs that were compiled for a different instruction set. Various parts are released under the BSD license, GNU Lesser General Public License (LGPL) or other GPL-compatible licenses. QEMU was written by Fabrice Bellard and is free software, mainly licensed under the GNU General Public License (GPL for short).
