Introducing M

M is a powerful and versatile formula language specifically designed for data manipulation and transformation. The term M is an informal designation. M’s official name is the Power Query Formula Language. For an explanation of this designation, see the History of M section later in this chapter. M is the language at the heart of Power Query, which is used in numerous applications like Microsoft Excel, Power BI, Power Platform, and Microsoft Fabric for data transformation and preparation.

The popularity of the M language has continuously grown over the last decade, and the language has been integrated into an impressive array of Microsoft tools and platforms. Today, M and Power Query are indispensable tools for modern data professionals such as business analysts, data scientists, and data enthusiasts.

This chapter is the beginning of your exciting journey that culminates in the mastery of the M language. We start with a brief history of M and then cover the basics of who, where, why, and how. Next, we introduce the absolute basics of the M language and finish with the formal and informal characteristics of M (in effect, what is M?). Overall, this chapter provides a firm foundation for the more in-depth exploration of the M language found throughout the rest of this book. Specifically, this chapter covers the following topics:

• The history of M
• Who should learn M?
• Where and how Is M used?
• Why learn M?
• M language basics
• The characteristics of M