Decubitus ulcers, commonly known as pressure sores or bedsores, are injuries to the surface of the skin and the underlying tissues caused by prolonged pressure. They usually occur on the heels, ankles, hips, and tailbone, which cover bony areas of the body. Prevention and treatment involve regular repositioning to relieve pressure, using support surfaces like special mattresses or cushions, and ensuring good hygiene and skin care. Advanced cases may require debridement, which removes dead tissue, or surgery to repair damaged tissue.