A novel series is a collection of related books that follow a continuous storyline or share common characters. Each book in the series can often be read independently, but they are best enjoyed in order, as they build upon previous events and character development. Popular examples of novel series include Harry Potter by J.K. Rowling and The Lord of the Rings by J.R.R. Tolkien. These series can span various genres, including fantasy, mystery, romance, and science fiction. Authors may choose to create a series to explore complex narratives or develop characters over time, allowing readers to become more invested in the story.