There were many popular online novels that could be used as reference: 1. Fantasy novels such as " Battle Through the Sky "," Martial Universe "," Covering the Sky ", etc. These novels usually depicted a world full of magic and technology. The protagonist constantly improved his strength through continuous cultivation and combat, and finally became a powerful existence. 2. Metropolis novels: For example," Silent Sheng Xiao "," A slight smile is very beautiful "," Shanshan is here ", etc. These novels mainly described the love stories in modern cities. The protagonists usually realized their dreams through their own efforts and struggles, and at the same time, they made many friends. 3. Science fiction novels such as " The Three-Body Problem,"" The Wandering Earth,"" Ball Lightning," etc. These novels depicted a universe full of technology and unknown worlds. Through exploration and adventure, the protagonists constantly discovered new technologies and human civilizations. 4. Historical novels: For example, Records of the Historian, Zi Zhi Tong Jian, Ming Dynasty, etc. These novels mainly described historical events and characters. The protagonist thought and interpreted history through his own experience and wisdom. 5. Detective novels: The Complete Sherlock Holmes, Night Walk, Murder of Time, etc. These novels reveal the truth hidden behind the events through suspense and reasoning. The above are just some common types. You still have to choose according to your personal interests and reading needs.