Most free software licenses are based on copyright, and there are limits on what kinds of requirements can be imposed through copyright. If a copyright-based license respects freedom in the ways described above, it is unlikely to have some other sort of problem that we never anticipated (though this does happen occasionally). However, some free software licenses are based on contracts, and contracts can impose a much larger range of possible restrictions. That means there are many possible ways such a license could be unacceptably restrictive and nonfree.
I may not know you, but I’d be willing to guess you’re a pretty good salesperson. You’ve probably said, “Put me in front of someone, and I can close them,” a time or two. I’ve come to notice that the biggest problem facing salespeople isn’t selling, it’s lead gen. You can be the best salesperson in the world, but if you don’t have prospects to sell to, it doesn’t matter.
Thus, free software means that computer users have the freedom to cooperate with whom they choose, and to control the software they use. To summarize this into a remark distinguishing libre (freedom) software from gratis (zero price) software, the Free Software Foundation says: "Free software is a matter of liberty, not price. To understand the concept, you should think of 'free' as in 'free speech', not as in 'free beer'". See Gratis versus libre.
Freeflys: Another strong contender in the freebies space, Freeflys has appeared on NBC’s Today Show, The Doctors, Fox News and a handful of other media outlets. Similar to most of these sites, Freeflys utilizes email alerts to tell users about free-sample offers as they happen. The site also allows you to search for a specific product with the handy search bar.