Raised bumps, also known as welts, are a common skin condition that can be caused by a variety of factors. They are characterized by raised, red, and often itchy bumps on the skin. These bumps can be caused by allergies, insect bites, or even certain medical conditions. Welts can also be caused by physical trauma such as friction or pressure. Treatment for welts depends on the cause, but may include topical creams, antihistamines, or other medications.