What is a Scam?

We all see the word, "Scam" all over the place. Some of us even use it ourselves. But do we really know what it is? I spent sometime looking it up. Here are some definitions of the word Scam: >From Cambridge International Dictionary of English: scam, noun [C] INFORMAL, a plan or action for making money which is dishonest, illegal and often clever. He burnt his own house down so that he could claim the insurance money - what a scam! >From the Merriam-Webster Dictionary: scam Main Entry: Pronunciation: 'skam Function: noun Etymology: origin unknown Date: 1963 : a fraudulent or deceptive act or operation (an insurance scam) >From The American Heritage