What's the Difference Between Free and Open Source?

When you get a bunch of people together and rit code, there's actually a lot of legal implications. The guy who helped design the storm trooper helmet for the original star wars went back and forth with several lawsuits because he would make products or moulds based off of those things that he made. And it just reminds me how lik complicated basically is open source software. If some does work, whether you pay them or not, for you, and produces something like who owns the thing, if you don't nail it down, can get really confusing.