* Undergraduate: Refers to a student pursuing a first degree at a university or college. This is typically a bachelor's degree (e.g., BA, BSc, BEng), earned after completing secondary education (high school). It's the foundational level of higher education.
* Postgraduate: Refers to a student pursuing a degree *after* they have already completed an undergraduate degree. This includes master's degrees (MA, MSc, MEng), doctoral degrees (PhD, EdD), and other professional qualifications at a higher level. It builds upon the undergraduate foundation with more specialized study and often involves research.
In short: Undergraduate is the first degree; postgraduate is any degree pursued after that first degree.