There was a time that the 32-volume Encyclopedia Brittanica (initially published in 1768 in 3 volumes) was revered as the definitive reference source — consistently cited by high school and college students writing scholarly papers. But everything changed on January 15, 2001 when Jimmy Wales and Larry Sanger launched Wikipedia, a free English-language encyclopedia, written and edited by thousands of editors and supported by the Wikipedia Foundation. January 15, 2016 marked Wikipedia’s 15th birthday. Its tremendous achievements can be quickly assessed by looking at Wikipedia by the numbers.
Number of articles (English language): 5,058,654 (as of 1-18-16))
Number of articles added per day: 800
Total number of articles (all languages): over 38 million
Number of registered editors (English language): 27,270,125 (of those 115,603 are active)
Percentage of female editors: 16.1% (2011)
Number of daily page views: Over 600 million
Number of month page views: 18 billion
Most visited page: Lists of death by year – 20.8 million page views)
Most heavily edited article: George W. Bush – 45,862 edits
Number of volumes if printed: If each volume contained 700 pages, Wikipedia would fill 7,473 volumes. The table of contents takes up 91 volumes.
Cost to print out the entire contents of Wikipedia: $500,000
Number of language editions: 291
Percentage of doctors who look up conditions: 50%
Largest area of topics: Culture and Arts (30%)
For further reading: https://en.wikipedia.org/wiki/Print_Wikipedia