free as free beer or free as free speech?

It is true that TeX / LaTeX are some of the oldest free software in existence, predating the Free Software movement, and it is reasonable to ask whether such distribution of software was unusual at the time and whether there were reasons for it. Nevertheless, the fact that “available even for paid Operati[ng] Systems as Windows or Apple” is rather irrelevant. Maybe you can start by reading this list and reconsider your question.

If you think you should give something back, you can make a donation to your TeX users group. They will spend the money in different TeX or typography elated projects

@Johannes_B I have read you are one of Latex3 project members so a more extense comment or answer would be good..I mean, I would like to understand what is the philosophy behind such a way of work

The Johannes B in the l3 project is a different Johannes:-)

@DavidCarlisle lol. Well but the important thing is what I believe (?. You are on the project also, isn't it?

yes I have been on the project since before we released latex2e, I joined in 1992 or so

I am not a team member :-)

To the close voters: why is this question unclear?

@CarLaTeX I really couldn't understand that also..

@HernanMiraola It is perfectly clear, in my opinion. Moreover it was upvoted by 7 users who judged it useful. I don't really understand why they're closing it (I voted to keep it open but it was not enough).

@CarLaTeX no problem, at least there is a good answer below with a long article for reading. Thanks..

I think people often do things without charge because setting things up to make a profit can be a royal pain in the ar$e. Plus, it makes them feel good not to do so. Also, it is liberating not to charge a fee, as one can give what they can of themselves without the guilt of a missed expectation that comes with the responsibility of charging a fee.

@StevenB.Segletes but what about this: do what you love. Why is necessary to be expecting a profit?

Well i think it is something wrong, people start living to pay [email protected]; and so, you do what is well paid. I mean, is contributes to that behaviour

Would you prefer working (i.e., being employed) in a technical area that you despise (or outside of technical areas altogether)? I would hope not. The most productive employees are those who love and take pride in what they do.

I don't prefer. But that's what happens to a big amount of [email protected] and of course it is not by choice. Anyway, is a quite complicated discussion..

I think this question is offtopic. It's free because of the license, period. The philosophical questions behind the choice of license do not belong here.

Well now we get to the crux...one chooses whether to work to live, or whether to worship money. Over the years, I've turned down promotions so that I could stay working in the research area I love. Not everyone makes that choice and some regret it years later.

@Raphael I think experience show it on-topic. But maybe you are right.