Online Analytical Processing (OLAP) is a kind of computer system that helps keep track of lots of data. It is like having a giant calculator that can organize, summarize, and analyze data. For example, let's say you want to know how much money you made last month. With OLAP, you can bring up a report that shows all the money you made, and how much of it came from each different thing you sold. It can help you figure out what products or services make the most money, so you can focus on those.