Free software is software that is meant to be shared. There is a strong movement behind free software that inspired other movements with its values and success.
Free software is software whose license guarantees the user the right to
- use his tool for whatever purpose, to
- study how it works, to
- share it with whoever he wants (under the same conditions) and to
- alter it (and also share the results) - to build on the work and help to improve it, for example.
There is a whole world of free software with software covering virtually every need.