A sharp increase in web encryption and a worldwide shift away from standalone websites in favor of social media and online publishing platforms has altered the practice of state-level Internet censorship and in some cases led to broader crackdowns, the Internet Monitor project at the Berkman Klein Center for Internet & Society at Harvard University finds. This study documents the practice of Internet censorship around the world through empirical testing in 45 countries of the availability of 2,046 of the world’s most-trafficked and influential websites, plus additional country-specific websites. The study finds evidence of filtering in 26 countries across four broad content themes: political, social, topics related to conflict and security, and Internet tools (a term that includes censorship circumvention tools as well as social media platforms). The majority of countries that censor content do so across all four themes, although the depth of the filtering varies.