I am a student in AP Calulus BC and I have been wondering this question for a while. I am doing the course online, and one lesson was called "Riemann Sums". The next lesson was "Numeric Integration".... and they were very similar. Why are they separated like this? Why wouldn't riemann sums just be included in the numeric lesson?

Are riemann sums a type of numeric integration? If not, what is the difference between riemann sums and numeric integration?