A column at osOpinion tries to explain the GPL by comparing it to recipes.
"Next time you cook a meal, pass a bookshop or eat at a restaurant, think it over. What sort of
recipe would you prefer? One that requires you to give it to anyone you cook the meal for, or
one that you can keep secret to yourself?
That's almost certainly the same way you feel about software licenses. But no matter what
Microsoft or Richard Stallman says, it is your choice what you use and neither can take that
away from you."