Yeah pretty much what other posters have said.

Quetiapine is Seroquel that is released pretty much faster into your system. This is usually taken at night (circumstances pending). It can aid sleep. As it can result in a much more rapid state of relaxation.

Seroquel XR is the extended release one. So it would take 24 hours to release in your system; again taken once a day. May be taken in a.m.