For quite a while, I thought that Free Software was Open Source Software. I've found out that this view is incorrect, and that Open Source Software is not necessarily Free Software. I honestly can't see any differences.
What am I missing here? What are the distinguishing traits of both parties?
This article should help:
http://www.gnu.org/philosophy/free-software-for-freedom.html
Both are basically the same, except the free software movement puts more emphasis on the freedom to modify and redistribute the code. For example, GNU GPL would be more "free" than MIT licence, because MIT license does not enforce copyleft and thus someone can develop closed-source software based on the code.
See also Wikipedia chapter about this, which mentions Microsoft shared source inititive, that can provide you with very unfree source code of their applications.
The GNU project answers this question directly:
http://www.gnu.org/philosophy/free-software-for-freedom.html
The essential difference, slightly oversimplified, is that Free Software generally requires that, if you modify and/or incorporate it into another body of work, the entire result must also be distributed as Free Software, and you are forbidden to further restrict the ability of any "downstream" users from modifying, using, or redistributing the software with the same rights that were given to you.
Disclaimer: Dammit, Jim, I'm a developer, not a lawyer. Don't construe any terms or comments as "legal advice."
Open source definition: http://opensource.org/docs/osd
Free software defintion: http://www.gnu.org/philosophy/free-sw.html
Both are talking about free-as-in-speech. FSF is "more free" in that for software to meet the FSF standards, it must afford more freedoms to its users. The OSI standards are looser, "free" software is "open" but the reverse isn't necessarily true - It turns out even this isn't always true.
They are functionally the same in the vast majority of cases. It's a philosophical difference - FSF wants intellectual freedom, OSI wants practical freedom to (re)use and adapt software.
Open source is a development methodology; free software is a social movement.
Freeware software is just small software which are free but their codes are not accessible.It can be downloaded ,used ,copied without restrictions.
Shareware software are just a demo version of the full software developed by small software company and the modification and other usability lies with the development group.Here end user dependencies is more.
Open source software are just software developed often by large vendors which are re distribuable ,used and modifiable with out any restrictions.Here codes of the software are fully accessed by the user for future modification and making of large software.