Fine lines and wrinkles are common signs of aging that develop as the skin loses firmness, elasticity, and hydration. They often appear in areas exposed to facial expressions or environmental stressors, such as the forehead, around the eyes, and mouth. These lines are a natural part of the aging process, but they can be exacerbated by lifestyle factors and environmental damage. While fine lines are typically shallow, wrinkles tend to be deeper and more pronounced.