A novella is a written work that is longer than a short story but shorter than a full-length novel. Typically, novellas range from about 20,000 to 40,000 words. They often focus on a single theme or character, allowing for a concise yet impactful narrative. Novellas are popular in various genres, including science fiction, romance, and mystery. They provide readers with a complete story experience in a shorter time frame, making them an appealing choice for those who enjoy a quick read without sacrificing depth or complexity.