Short answers, pulled from the story.
The Encyclopædia Britannica was first published in serial instalments between December 1768 and about August 1771 in Edinburgh, Scotland. The instalments came together to form three volumes. It continued in print for 245 years, making it the longest-running in-print encyclopaedia in the English language.
William Smellie compiled nearly all of the first edition himself, drawing heavily on Scottish sources. He had minor assistance from at least one contributor, James Anderson, who wrote the articles on "Dictionary," "Pneumatics," and "Smoke." Smellie was engaged by the publishers Colin Macfarquhar and Andrew Bell.
In March 2012, Britannica's president Jorge Cauz announced the company would cease printing the encyclopaedia. The 2010 15th edition, a 32-volume set, was the last printed edition. Since 2016, the Britannica has been published exclusively online at Britannica.com.
A 2005 study by the journal Nature found 162 errors in Wikipedia and 123 in the Britannica across 42 reviewed science articles, an average of 3.86 mistakes per article for Wikipedia and 2.92 for Britannica. Both sites had four serious errors each. Britannica disputed the study's methodology and called for a retraction; Nature declined.
The 15th edition, introduced in 1974, divided the encyclopaedia into the Micropædia (12 volumes of short articles), the Macropædia (17 volumes of long articles, ranging up to 310 pages), and the Propædia (a single volume outlining all human knowledge). A two-volume index was eliminated from the initial release and restored in 1985 after widespread criticism.
The Britannica's 4,411 print contributors include Nobel laureate economist Milton Friedman, astronomer Carl Sagan, and surgeon Michael DeBakey. Albert Einstein, Marie Curie, and Leon Trotsky have all appeared among its authors. Christine Sutton of the University of Oxford contributed 24 articles on particle physics, making her one of the most prolific contributors.