Two dimensional (2D) materials have attracted significant attention in the past decade for their high application potential to address some of society’s most pressing issues such as energy storage and the scarcity of potable water. One of the latest, and relatively large, family of 2D materials is transition-metal carbides and nitrides, called MXenes. Since the initial synthesis of Ti₃C₂ in hydrofluoric acid in 2011, almost 30 other new compositions and at least eight different synthesis pathways have been reported. In this review, we overview the structure, synthesis, and chemistry of MXenes, with examples of their properties and potential applications that partially explain why these materials have become so popular.