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The July Write-a-Thon is Wednesday! Our theme is Biographies. On Wednesday, July 2nd we're inviting all Citizens to come to the wiki, start a new article, and edit somebody else's new article. It's a Write-a-Thon! It's a wiki-whoopie, a cyber-social, a collaborative kegger! Are you new? That's a good day to get a Quick Start!

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A new wiki encyclopedia project—and more! We aim at reliability and quality, not just quantity. We welcome collaboration with everyone who has knowledge, broad or narrow, about any of the world's innumerable subjects. We write under our real names—and are both collegial and congenial. We now have [[:Category:CZ Live|Template:Articles number+ articles]] and are gathering speed. Eduzendium participants write for academic credit. Write for the Citizendium—knowledge is fun! Sign up—we need both authors and editors (you might be both!) Then, get a quick start. Remember, we are an open, young project—it's easy to get involved! Learn about us Why Citizendium? For readers: About | FAQ For contributors: Authors | Editors | How to collaborate For the press Important new community pages WatchKnow will be a free, non-profit, K-12 educational video contest, currently under planning and development. Myths and Facts: we might be different than you think! We are organizing Workgroup Weeks--our biggest initiative yet. Citizens, get involved, and watch our numbers multiply! Support us Our mission is educational, non-profit, global, and free. Shop at our Amazon.com and Barnes & Noble links and we'll get donations at no cost to you. Link to us so search engines can better find us.   (CC) Photo: Tanya Puntti Each sentence you add is another drop in an expanding sea of words.

Some of our finest [ about ] Approved Articles Developed Articles (over 800) Share your knowledge. It's a way to achieve immortality. —Often attributed to the Dalai Lama Article of the Week [ about ] (PD) Image: Library of Congress Augustin-Louis Cauchy around 1840./ Lithography of Zéphirin Belliard after a painting by Jean Roller. Augustin-Louis Cauchy (Paris, August 21, 1789 – Sceaux, May 23, 1857) was one of the most prominent mathematicians of the first half of the nineteenth century. He was the first to give a rigorous basis to the concept of limit. His criterion for the convergence of sequences defines sequences that are now known as Cauchy sequences. This notion has led to the fundamental mathematical concept of a complete space. The Cauchy condition for the convergence of series can be found in any present-day textbook on calculus. Probably Cauchy is most famous for his single-handed development of complex function theory, with Cauchy's residue theorem as the fundamental result. Cauchy was a prolific writer, he wrote approximately eight hundred research articles and five complete textbooks. He was a devout Roman Catholic, strict (Bourbon) royalist, and a close associate of the Jesuit order. [more...] New Draft of the Week [ about ] Sea Glass Sea glass is formed when broken pieces of glass from bottles, tableware, and other items that have been lost or discarded are worn and rounded by tumbling in the waves along the shore of oceans and large lakes. The most common varieties are green, brown or clear, while other colors, such as orange, red, yellow, cobalt blue, purple, turquoise, and black are much more rare in genuine sea glass. Genuine sea glass often shows signs of "hydration", a process by which the soda and lime in the glass are slowly leached out through constant contact with water, and may be easily distinguished from artificially tumbled glass by a trained eye. Sea glass has become more rare in recent decades as a result of stricter laws against littering, but may still be found along the shores of oceans and lakes world-wide. [more...]