Hair loss or alopecia is one of the most troublesome disorders for adults and children, because physical appearance is so important to our society. The importance of the patient's cosmetic problems should not be underestimated. Alopecia can be linked to a variety of causes. Sedation and education are best treated in some cases, while others require medical examination and therapy. This book explores the causes of hair loss with a focus on the most common ones adrogenetic alopecia, telogen effluvium, alopecia areata, and drawn alopecia