Recent demonstrations and violent attacks have highlighted the need for an improved understanding of the role of internet-based technologies in aiding and amplifying the spread of extremist ideologies. Since the early days of the internet, radical groups and movements across the ideological spectrum have demonstrated their intent and ability to harness virtual platforms to perform critical functions.

This Perspective, the second in a RAND Corporation series on online white-supremacist and violent misogynist material, provides a primer on how the internet influences the activities of radical groups and movements and how exposure to or consumption of extremist content online influences the behavior of internet users. After briefly discussing relevant terminology, the authors describe the role of the internet in facilitating five operational functions for radical groups and movements: (1) group financing; (2) networking and coordination; (3) recruitment and radicalization; (4) inter- and intra-group knowledge transfer; and (5) planning, coordination, and execution of harmful online and offline operations. The authors then examine how virtual interactions can facilitate or encourage users’ adoption of extremist ideas and inspire or alter offline behavior. The Perspective concludes with a discussion of how the internet can be leveraged as a tool to counter extremism, and the authors provide suggestions for further research.