This new legal ground has allowed sports gambling to grow into a massive industry in just a few years. Some allow bets to be placed online, for example, while others only allow in-person gambling. Today, more than 30 states and Washington, D.C., permit sports gambling in some form, but the specifics on how and where those bets can be made varies dramatically. It took less than a month for the first state to begin allowing sports wagers and a flood of states quickly followed suit.
