Definition of Free Software

A program is free software if you as the user have
the four essential freedoms. The freedom to:

- run the program as you wish, for any purpose.
- study how the program works, and change it so it does
  your computing as you wish.
  Access to the source code is a precondition for this.
- redistribute copies so you can help your neighbor.
- to distribute copies of your modified versions to others.

https://www.gnu.org/philosophy/free-sw.html