Smart clothing is the next evolutionary step in wearable devices. It integrates electronics and textiles to create functional, stylish and comfortable solutions for people's daily needs. The concept includes not only clothing, which is a covering mechanism for the body but also has the function of tracking body indicators in certain situations. The review introduces the classification and concept of smart clothing, the application areas such as sports, workwear, healthcare, military and fashion. It will also outline the current state of smart clothing and the latest developments in the field, and discuss future developments and challenges.