Wikipedia turns 20 today

What began as a free alternative to World Book and Encyclopedia Britannica has become one of the biggest repositories of basic information and a testament to the power of the open web.

Why it matters: Almost no one has a traditional set of encyclopedias anymore. As Wikipedia turns 20 today, it's worth taking a look at the rise of the massive site and the impact it has had.

Flashback: Wikipedia debuted on Jan. 15, 2001, as the brainchild of Jimmy Wales and Larry Sanger, who gave the site its name, a portmanteau of wiki — derived from the Hawaiian for "quick" and then already in use to refer to a family of user-editable websites — and encyclopedia.

By the numbers:

• Wikipedia is among the top 15 sites on the internet.
• There are 55 million articles, across 300 languages.
• More than 280,000 volunteers help add to the site and keep it updated.
• Wikipedia is edited 350 times per minute and read more than 8000 times a second. 
• Wikipedia is accessed by 1.5 billion unique devices every month and read more than 15 billion times every month. 
• Roughly 89% of articles on Wikipedia are in languages other than English. 
• Most vandalism (edits that do not meet Wikipedia’s reliability and neutrality standards) is addressed within five minutes on Wikipedia. 
• Wikipedia is supported by nearly 7 million donors, with the average donation being about $15.

Between the lines: In a world where basic facts are often the subject of partisan disagreement, Wikipedia has emerged as the rare site that is widely trusted across ideological lines and is also a go-to for populating information panels on Google and other major search and portal sites.

• "We're about building a shared understanding of the world together," Wikipedia founder Jimmy Wales said on a conference call with journalists. "We want to bring everyone together for a thoughtful discussion and debate, to understand the world, to learn before having an opinion. And we know how to have difficult conversations on hard topics.”

Yes, but: Wikipedia has plenty of notable weak spots, including the lack of diversity among those who edit pages.

• That translates to a fair amount of blind spots, especially for people of color, trans people and those from other underrepresented groups.
• And, while generally a reliable source of information on many topics, it can be unreliable at any given moment on any topic. Its strongest virtue — that anyone can edit it — can also be its biggest weakness.