Bochs [ bɔks ] is a free x86 and AMD64 emulator and debugger, which is subject to the terms of the LGPL.

Many operating systems such as Windows or Linux can be operated under Bochs. Also Bochs is available for many different operating systems.

Bochs also serves as a platform to develop as an operating system or hardware-related applications for a PC and test. The aim of the developer is to achieve a complete PC - compatibility. Since Bochs does not execute directly but as a pure emulator machine instructions, the execution speeds are correspondingly lower than in virtual machines like VirtualBox, VMware Workstation or Virtual PC.

Boch is able to emulate at a non- x86 an x86 processor. So you can use on a Sun SPARC processor an x86 host system such as Windows, for example, under Mac OS X on the Apple Macintosh on a PowerPC processor, or Solaris.

In the meantime, variants have emerged, such as the port of Bochs on the PlayStation Portable, the iPhone or the GP2X.