A compound sentence is a type of sentence that contains at least two independent clauses joined by a coordinating conjunction (such as "and," "but," "or," "nor," "for," "so," or "yet") or a semicolon. Each independent clause can stand alone as a complete sentence, but when combined, they create a compound sentence that expresses a more complex idea.
Example: "I wanted to go for a walk, but it started to rain."
In this example, "I wanted to go for a walk" and "it started to rain" are both independent clauses.