DAX is the formula language embedded within Power BI Desktop, PowerPivot and Analysis Services (Tabular Model). See below for Wise Owl resources which can help you learn DAX!
Other DAX resources
We believe classroom training is the best way to learn DAX, but we've included lots of other DAX training resources below just in case you don't agree!
Other DAX training resources
Try our DAX exercises
Videos on DAX
The following videos cover DAX (as part of other software applications):