1.1 WHAT IS A TOPIC?

A topic is a noun phrase that expresses what a sentence is about, and to which the rest of the sentence is related as a comment.
Another definition of a topic is: Topic is another word for subject. It answers the question, “Who or what is the paragraph (or article) about?” The topic is stated as a single word or phrase—not a complete sentence. see link

1.1.1. IDENTIFYING THE TOPIC SENTENCE