Teo is an emulator of the Thomson TO8 microcomputer for PC, running on MSDOS, Windows and Linux.
The compatibility is close to 100% for softwares which don't use non emulated peripherals and don't hold physical protections.
Teo acts just like a real TO8, in order to use it you will have to be familiar with the the command line. It also uses a AZERTY keyboard which can be confusing to those who don't have one.