If you board the monorail at one of the resorts, it will be the resort monorail. The other MK monorail (I think they call it the express monorail) goes past all of the resorts, but it doesn't stop. It just goes in between the TTC and MK. If you're at the TTC, you'll see signs telling you which is which. The Epcot monorail is also at the TTC, and it goes between Epcot and TTC with no other stops.