Power Query M formula language
Microsoft Power Query provides a powerful data import experience that encompasses many features. Power Query works with Analysis Services, Excel, and Power BI workbooks. A core capability of Power Query is to filter and combine, that is, to mash-up data from one or more of a rich collection of supported data sources. Any such data mashup is expressed using the Power Query M Formula Language. It's a functional, case sensitive language similar to F#.
Power Query M functions
Get detailed information for any of the over 700 M functions in the Power Query M formula language.
M quick tour
Get the big picture. This takes you on a quick tour, describing the most essential concepts in M.
Power Query M language specification
The specification describes the values, expressions, environments and variables, identifiers, and the evaluation model that form the Power Query M language’s basic concepts.
Expressions, values, and let expression
A Power Query M formula language query is composed of formula expression steps that create a mashup query. This article describes the most fundamental elements of an M expression.
Power Query M type system
The Power Query M formula language document describes the M type system.
Power Query M evaluation model
Learn about the Power Query M evaluation model.