Encyclopedia.com!

Everipedia removed some of the more annoying aspects of Wikipedia and created a site that is much easier to use. Notability requirements are eliminated and citations / editing are WYSIWYG. There is also a commenting page for each link or file added.

The Encyclopædia Britannica is a general English-language encyclopaedia published by Encyclopædia Britannica, Inc., a privately-held company. The articles in the Britannica are aimed at educated adult readers, and written by a staff of about 100 full-time editors and over 4,000 expert contributors. It is widely regarded as the most scholarly of encyclopaedias. Software versions include Britannica Ultimate Reference CD or DVD, Britannica Deluxe CD or DVD and Britannica Online.

Reference.com offers a massive online dictionary, thesaurus, encyclopedia, quote finder, and translator (powered by Google Translate)- all for free. For the Dictionary.com and Thesaurus.com mobile app, go here. Dictionary.com

Infogalactic is an Internet-based, free-content encyclopedia project that is a dynamic fork of Wikipedia and improves upon the online encyclopedia's model of openly editable content. Infogalactic's pages are interlinked in order to connect the user to related pages with additional information, and are categorized in a variety of ways, including Relativity, Notability, and Reliability to allow the user to prioritize his personalized perspective

Wikipedia, better than ever—on iPhone, iPad, and Apple Watch. Discover the world and enjoy beautiful typography with this sleek app.

Newslines lets people create shared timelines on any person, product or news event. Writers create news snippets that are combined into interactive multimedia timelines.

Alchetron.com is a free social encyclopedia for world where you can create, organize and learn easily using topics.

Dictionary from the Elementary project.

Oppia is a free, open-source learning platform. Full of interactive activities called 'explorations', Oppia helps curious minds learn and teach.

Stubia is a mobile encyclopedia that limits each article to 160 characters: this limitation makes each topic easy to understand.

A wiki-based encyclopedia, the primary difference between Citizendium and Wikipedia being that Citizendium has "subject matter expert" editors, chosen by the community to validate pages and content.

Wikipedia is probably the single largest, most comprehensive and simply best information resource out there on the Internet - a really great resource.many people though would like to have access to this giant resource when they're not plugged into the Internet.