The Open Source Definition is used by the Open Source Initiative to determine whether or not a software license can be considered open source.

The definition was based on the Debian Free Software Guidelines, written and adapted primarily by Bruce Perens.

Text of the Definition

Free Software Definition vs Open Source Definition

Despite the fundamental philosophical differences between the free software movement and the open source movement, the official definitions of free software by the Free Software Foundation and of open source software by the Open Source Initiative basically refer to the same software licenses, with a few minor exceptions. While stressing the philosophical differences, the Free Software Foundation comments:

See also

• Comparison of free software licences

• The Free Software Definition

• Debian Free Software Guidelines