This chapter presents a comprehensive classification of self-healing materials, highlighting their mechanisms, properties, and applications. The materials are categorized into polymers, composites, ceramics, and metals, each offering unique advantages and facing specific challenges. Polymers excel in healing efficiency, composites combine structural strength with healing capabilities, ceramics overcome brittleness for biomedical and protective applications, and metals demonstrate durability in high-stress environments. Hybrid and multifunctional systems are discussed as emerging innovations that integrate diverse materials and mechanisms. Future directions focus on improving scalability, sustainability, and integration with advanced technologies, showcasing the transformative potential of self-healing materials in various industries.