fsherfy said “Still new here could someone please explain boost compatible to me. I l think it has to do with wider wheel hubs. I.e. Longer axles. But not sure. Thanks.”
Yes, that’s correct. Boost is a relatively new standard that came around due to the plus-size tires (29+, 27.5+) that came out in recent years. It means that the frame (or fork) is wider between the dropouts. Wider spacing allows for wider hubs and wider rims without sacrificing wheel strength. With traditional dropout spacing, ever-wider rims meant decreasing wheel strength due to the angle of the spokes. By going to wider dropouts/hubs, the rims can be quite wide without compromising strength. So, if you’re in the market for a new bike and think you might want to try out plus-size tires, then getting a frame and fork with Boost spacing is the way to go.