Possible Clues:

• Popular online reference
• Online reference source
• Much-visited website run by a nonprofit foundation
• Resource with content in 300+ languages
• Major online reference source
• Internet encyclopedia created by its users
• Many teachers disallow it in footnotes
• Having confused 'kepi' with 'wadi', I seek clarification here
• Its symbol is a globe composed of jigsaw puzzle pieces
• Popular reference work