Maiden is usually for a rider in their first or 2nd year of showing. Novice horse/rider is usually for a first year horse or rider. You get a little screwed sometimes because they'll put a thing on the billet that says something like hasn't run a blue ribbon... which means there will be people more qualified in that class... but it's all for fun in the beginining anyway right?
"Be a best friend, tell the truth, and overuse I love you
Go to work, do your best, don't outsmart your common sense
Never let your prayin knees get lazy
And love like crazy"