FMSLogo is a free implementation of a computing environment called Logo, which is an educational interpreter language.

GUI and Extensions were developed by George Mills[1] at MIT.

FMSLogo also supports a windows interface thus I/O is available through this GUI- and keyboard and mouse events can trigger interrupts.

FMSLogo evolved from MSWLogo: An Educational Programming Environment, a free, open source implementation of the Logo programming language for Microsoft Windows.

It is released under the GPL and is mainly developed and maintained by David Costanzo.