In sports betting, the term "BTTS" refers to "Both Teams to Score".
This one is fairly straightforward. Do you think that both teams will score in a game? If so, you'd want to bet the "Yes".
Do you think that one or both of the teams WON'T score in a game? If so, you'd want to bet the "No".
-
For instance, let's say that Chelsea is playing Manchester City. You might see a line that says something like this:
Both Teams to Score?
Yes, 1.85
No, 2.25
In this case, the "Yes" side is a slight favourite, while the "No" side is a slight underdog. Chelsea and Man City both have pretty potent offences, which is why the bookmakers would assign this line as a slight favourite to win.