As a fan of online novels, I can tell you some of the types and topics that readers like. The following are some common novel types and topics: 1. Fantasy novels: Fantasy novels usually involve magic, mythology, martial arts, and other elements. The plot is complicated and there are many characters. 2. urban novels: urban novels mainly describe the protagonist's life and work in the modern city, usually involving love, friendship, workplace and so on. 3. Historical novels: Historical novels usually use historical events as the theme to describe the life and struggles of the protagonist in different historical periods. 4. Science fiction: Science fiction usually uses technology as the theme to tell the story of the protagonist exploring the future world through technological means. Romance novels: Romance novels usually describe the love story of the protagonist, involving romance, emotions, family, and so on. Horror novels: Horror novels usually use horror elements as the theme to describe the protagonist's path to survival in a terrifying environment. These are just some of the common types of novels. The readers 'preferences vary according to their personal interests and reading preferences. There are many other types of novels.