ABCD is an acronym that can refer to various concepts depending on the context. In education, it often stands for a method of writing learning objectives: Audience, Behavior, Condition, and Degree. This framework helps educators clearly define what students should achieve and how their success will be measured. In healthcare, ABCD can refer to a system for assessing moles for signs of skin cancer. The letters stand for Asymmetry, Border, Color, and Diameter. This method aids individuals in identifying potentially harmful skin changes that may require further evaluation by a medical professional.