Anonymous identifies an amorphous entity that has been active on the Internet and beyond from 2003 onward. It is a collective label, and a related set of symbols, adopted by several groups and individuals for a variety of goals, ranging from pranking to political activism. Three phases in the evolution of Anonymous can be identified, from prank-oriented activities to explicitly political ones. Its tactics embrace a combination of disruptive actions in the digital realm and beyond, and its nature reflects closely the properties of the digital environment where it operates.