Everyone who has dabbled around with Power BI knows probably the concept of measures (if not, here’s a good refresher). Measures are calculations using the DAX formula language (which kinds of resemble Excel formulas, at least the easy calculations do). They are calculated on-the-fly whenever they are used in a visual such as a chart or a table. In the following matrix, the results of a measure are indicated with the red box:
Measures are calculated on-the-fly because it’s virtually impossible to pre-calculate every possible combination of dimension members. They are an important pillar of your Power BI semantic