Dimension Table

A dimension table is a table that stores details about the facts. Dimension tables contain attributes that describe fact records in the fact table.

A dimension table typically has two types of columns, primary keys to fact tables and textual/descreptive data. Commonly used dimensions are customers, products, and time
For an example, consider this: If I just say… “20kg”, it does not mean anything. But if I say, "20kg of Rice (Product) is sold to Ramesh (customer) on 5th April (date)", then that gives a meaningful sense. These product, customer and dates are some dimension that qualified the measure - 20kg.