1. Introduction 2. Thermal energy storage methods 3. PCMs classification 4. Low and high temperature PCMs 5. Multifunctional PCMs 6. Encapsulation and packing of PCMs 7. Shape stabilized and form stable PCMs 8. PCMs in biomedical applications 9. Smart textiles with PCMs for thermoregulation 10. Electric and electronic applications 11. PCMs in buildings 12. PCMs in chemical and process engineering (thermal (nano)fluids, heat pumps, water tanks, etc.) 13. Cooling packing and cold energy storage 14. Fire retarded PCMs 15. Future trends 16. Conclusions