Compound Sentence - 

also called COORDINATED SENTENCE

Subject + predicate + FAN BOYS (conjunction)+ Subject + Predicate.

1. When two sentences are joined by a conjuction or connective device, they are not longer called SENTENCES but CLAUSES each one.

2. A compound sentence is only one sentence with two clauses join by a FAN BOY (also called conjuction or connective device)

3. They are called coordinating clauses because each clause is INDEPENDENT. This means that if you put a PERIOD after each clause and remove the FAN BOY (conjunction), the clause has a COMPLETE MEANING and it stands by itself  (it makes sense).