Power Query M Language Editor Power Query (Get & Transform) uses the M language to allow you to customise and build in flexibility to your queries. Currently writing the M language is tricky to write. It is case sensitive and there is no built-in help to assist you using the language. Apparently Microsoft is working on creating an M editor, but there is no time line on when it will be ready. This article takes you through some steps to create your own editor using Notepad ++. If you use Power Query a lot then this may be worthwhile.