The Encyclopædia Britannica was first published between 1768 and 1771 in Edinburgh, Scotland, making it the oldest English-language general encyclopedia. Over the years, it evolved through multiple editions, notably adopting a continuous revision model in 1933 and transitioning exclusively to an online format in 2012. The paid subscription provides more thorough articles than the free online version, and it also includes multimedia resources and a bunch of convenient features, like pre-formatted bibliographic references in MLA, APA and Chicago styles.