This document discusses the history and fundamentals of microfluidics. It begins with a brief history of microfluidics starting in the 1950s and developments in microelectronics, MEMS, and early microfluidic devices in subsequent decades. It then defines microfluidics as handling small fluid volumes typically on the microscopic scale and discusses commercial and scientific applications of microfluidics like human genome sequencing, medical diagnostics, and new chemical reactions. Key milestones are also outlined such as miniaturization of devices in earlier decades and exploration of new effects and applications in more recent decades.