Exactly. When you go to Woodbine, it is single-event sports betting, because it's the outcome of a single race, and it's parimutuel betting, which is pool based, and the odds that you see are not fixed. Those odds will change up until the point that the race starts. You can place your bet five minutes before the race starts and then the odds will change after you've placed your bet. Once the race starts, it's essentially locked down.
I defer to Ms. Foss if I've missed any of the details there, but that's my understanding of the difference.