An open source analogy: Open source is like sharing a recipe

Imagine you’ve baked something for your friends—a loaf of bread, perhaps. By sharing this bread with your friends, you’ve given them something that not only sustains them, but also strengthens your relationship with them. Certainly, these are valuable gifts. 

But what if you share more than the finshed product? Suppose that in addition to the loaf of bread, you also give your friends the recipe for that bread. Now you’ve given them something even more valuable: the power to reproduce the gift