Wikipedia[note 3] is a multilingual free online encyclopedia written and maintained by a community of volunteers, known as Wikipedians, through open collaboration and using a wiki-based editing system. Wikipedia is the largest and most-read reference work in history.[3] It is consistently one of the 10 most popular websites ranked by Similarweb and formerly Alexa; as of 2022, Wikipedia was ranked the 5th most popular site in the world.[4] It is hosted by the Wikimedia Foundation, an American non