Public interest and policy debates surrounding the role of the Internet in terrorist activities is increasing. Criminology has said very little on the matter. By using a unique data set of 223 convicted United Kingdom–based terrorists, this article focuses on how they used the Internet in the commission of their crimes. As most samples of terrorist offenders vary in terms of capabilities (lone-actor vs. group offenders) and criminal sophistication (improvised explosive devices vs. stabbings), we tested whether the affordances they sought from the Internet significantly differed. The results suggest that extreme-right-wing individuals, those who planned an attack (as opposed to merely providing material support), conducted a lethal attack, committed an improvised explosive device (IED) attack, committed an armed assault, acted within a cell, attempted to recruit others, and engaged in non-virtual network activities and non-virtual place interactions were significantly more likely to learn online compared with those who did not engage in these behaviors. Those undertaking unarmed assaults were significantly less likely to display online learning. The results also suggested that extreme-right-wing individuals who perpetrated an IED attack, associated with a wider network, attempted to recruit others, and engaged in non-virtual network activities and non-virtual place interactions were significantly more likely to communicate online with co-ideologues. Policy Implications Collectively the results provide insight into violent radicalization as a whole and not just into violent online radicalization. The results also largely confirm the results found in von Behr, Reding, Edwards, and Gribbon (2013) and in Gill and Corner (2015). The current study and the two previous studies have tackled these questions by using numerous methodological approaches and data sources and have arrived at similar conclusions. The Internet is largely a facilitative tool that affords greater opportunities for violent radicalization and attack planning. Nevertheless, radicalization and attack planning are not dependent on the Internet, and policy needs to look at behavior, intentions, and capabilities and not just at beliefs. From a risk assessment perspective, the study also highlights the fact that there is no easy offline versus online violent radicalization dichotomy to be drawn. It may be a false dichotomy. Plotters regularly engage in activities in both domains. Often their behaviors are compartmentalized across these two domains. Threat management policies would do well to understand the individuals’ breadth of interactions rather than relying on a dichotomous understanding of offline versus online, which represent two extremes of a spectrum that regularly provide prototypical examples in reality. A preoccupation with only checking online behaviors may lead an intelligence analyst to miss crucial face-to-face components of a plot's technical development or a perpetrator's motivation. Policy and practice may benefit from adopting insights from emerging research arguing in favor of disaggregating our conception of the “terrorist” into discrete groups (e.g., foreign fighters vs. homegrown fighters, bomb-makers vs. bomb-planters, and group-actors vs. lone-actors; Gill and Corner, 2013; LaFree, 2013) rather than disaggregating the radicalization process into discrete groups (e.g., online radicalization and prison radicalization). We need to understand the drives, needs, and forms of behavior that led to the radicalization and attack planning and why the offender chose that environment rather than purely looking at the affordances the environment produced. By looking at the Internet as an affordance opportunity that some forms of terrorist or terrorist violence require more than others do, the focus is shifted from the radicalization process toward an understanding of how crimes are committed. In other words, we are looking at crime events rather than at the underlying dispositions behind the criminality.