lawn tractor

What is the difference between the LT and LX models. Also the GT vs. GX.

Might not be the right sub-forum for this, but hoping this works as a general "catch all"... Just finished seeding and strawing the lawn for our house build (hope to close/move in in 3 weeks or so). Doing it all by hand, I'm well aware of how much lawn I'm going to have to mow in the future...