Pivot Tables are used to summarise data that appear as a list. The summary structure is easy to make, by dragging and dropping fields graphically.
All lists must have field headings, and fields in the list can be of two types:
Data: which will contain a value. Field names like amount, total, or salary are commonly used as data fields.
Category: which will describe the data. So fields like Date, OrderID, or SalesPerson might be category fields, because they can be used to describe the data in an amount, total or salary field.
Have a look at these videos (linked below). When you have done this, try and create a pivot table yourself.