Microwave ovens are so common now that we don't really think about them much. We just appreciate the fact that they cook food fast. Back when they were first catching on in popularity, though, there were a lot of public misgivings about them. Could they cause cancer? Could you get some sort of radiation poisoning from them? Fortunately, the answer to both of these questions was "No" and now we enjoy our microwave popcorn in peace.