The concept of multidimensional cube is a good way to help users understand how they may want to query the multidimensional database or create OLAP reports. The dimensions of a cube are stored in a database table.
The data cube in the diagram below is composed of there dimensions: Customer, Product and Time.

This cube would allow query BY customer, BY time and BY product. Hence, sample query could be selecting a customer BY time and BY Product.
Additional dimensions (e.g. sales territory, sales person, etc) increase the size of the cube geometrically.