Keratins are a family of fibrous proteins that are key structural components in various tissues of the body, particularly in the skin, hair, and nails. They provide strength and resilience, helping to protect cells from damage and dehydration. Keratins are classified into two main types: soft keratins, found in skin and hair, and hard keratins, found in nails and the outer layer of skin. These proteins are produced by specialized cells called keratinocytes, which are primarily located in the epidermis of the skin. Keratins play a crucial role in forming protective barriers, making them essential for maintaining the integrity and health of epithelial tissues.