The literature shows that there are two fields that can feed radicalization, online and offline domains. However, the arbitrary separation has been challenged since radicalised individuals use both domains for their activities and they seamlessly move across the two (Pauwels & Schils, 2016; Gill et al., 2017; Whittaker, 2022). Furthermore, most scholars today agree that radicalization is not a linear or a step-by-step process, but rather a multifactorial phenomenon (Frissen, 2021), where different mechanisms operate in different ways for different people in different contexts (Borum, 2011). This report presents the main theories and ways radical groups influence and attract individuals online, and the most common tools and strategies governments use to counter its impact.