A subfamily is a taxonomic rank in biological classification that is one level below a family and one level above a genus. It groups together related organisms that share common characteristics and evolutionary traits. For example, in the classification of cats, the subfamily Felinae includes domestic cats and wild cats, distinguishing them from other families like Canidae, which includes dogs. Subfamilies help scientists organize and understand the diversity of life on Earth. By categorizing species into subfamilies, researchers can study their relationships, behaviors, and ecological roles more effectively. This hierarchical system aids in the identification and classification of organisms within the broader context of taxonomy.