Gambling is an ancient human activity. We indulge ourselves by allowing ourselves to experience the dangers and thrills of chance in a somewhat controlled way. The history of lotteries and related games is explored. The chances of drawing various poker hands are laid out. The role of probability in horse racing is described, and how the odds quoted are not strictly statements of probability, but terms on which business is to be done. Political prediction betting markets give us a further interpretation of probability as a way of expressing strength of opinion in a quantifiable, albeit flawed way. Wagers encourage boasters to put their money where their mouth is, and so to quantify their degree of belief.