You're probably expecting something like Monopoly to walk away with the prize as the most popular board game ever, but that's actually not the case. Rather, chess (yes, chess) is one of the best-selling board games of all time.
It makes sense when you stop and think about it. Chess has been around for hundreds of years, and its timeless mechanics never go out of date. Plus, anyone can make and sell a chess set. As such, there more more on the market right now than any of us could ever hope to count.