Skin and hair diseases include a wide range of conditions that affect the skin, scalp, and hair. Common skin conditions include acne, eczema, psoriasis, and dermatitis, while hair conditions may include alopecia, dandruff, and fungal infections. These disorders may be caused by genetics, infections, autoimmune reactions, or environmental factors. Symptoms may include rash, itching, inflammation, hair loss, or flaking. Prompt diagnosis and treatment by a dermatologist or trichologist are essential to managing these conditions and maintaining healthy skin and hair.