What does it mean for a clarinet to have a "simple key system?"?

Question

better yet, tell me if the bundy 577, a clarinet similar to most middle school band clarinets, follows the simple system (*the simple system is also called the albert system*)

Answer 1

im just taking a stab here, but maybe its a professional model clarinet with revised key mechanisms, like a  superaction 80 selmer saxaphone.....

Answer 2

It means Albert System. Don't let the name fool you. It's called "Simple" because it has fewer keys, but it is much harder to learn and play- it requires some very uncomfortable finger positions. Bundy clarinets do not use this system, in fact very few modern clarinets use it. The Albert System is not useful for anyone taking band lessons.