Dilation and Curettage (D&C) is a medical procedure used for both diagnostic and therapeutic purposes. It involves dilating the cervix and removing tissue from the uterus lining, which can be done for various reasons, including diagnosing uterine conditions, treating abnormal bleeding, or removing nonviable pregnancy remnants. D&C can be performed in both pregnant and nonpregnant patients and is commonly used in obstetrics and gynecology.