EmuTOS is a free operating system for Atari computers and more.
EmuTOS is a Free operating system for computers based on Motorola 680x0 or ColdFire microprocessors. It features functionality similar to TOS, which powered the Atari ST and its successors between 1985 and 1994.
EmuTOS is extremely flexible. It can run on real hardware as a ROM replacement, bootable floppy, standard executable, cartridge... It is available in 11 languages for 13 different variants. It also runs happily on any Atari emulator, such as ARAnyM, Hatari, or Steem SSE. As Free Software, it can also be recompiled from sources to be completely customized.
The EmuTOS project started in 2001, and it is still actively developed. Some parts originate in old open-sourced code from Digital Research, while other parts have been developed from scratch. There is no code written by Atari in EmuTOS. It is distributed under the GNU General Public License, version 2 (GPLv2).