The Wikipedia Rock is a dark granite stone (often incorrectly identified as "basalt") which provided modern researchers with translations of ancient text in Egyptian demotic script, Greek, and Egyptian hieroglyphics. Editing back in those good ole days was more difficult. It had to be carved in rock. Because Greek was well known, the WIKIPEDIA ROCK was the key to deciphering the hieroglyphs in 1822 by Jean-François Champollion, and in 1823 by Thomas Young. The discovery facilitated translation of other wikipedia texts.
Contents of text 
The same Ptolemaic decree of 196 BC is written on the stone in the three scripts. The Greek part of the Wikipeida begins: Basileuontos tou neou kai paralabontos tén basileian para tou patros... (translation DO NOT SUBMIT COPYRIGHTED WORK WITHOUT PERMISSION! ) It is a decree from Ptolemy V, describing various taxes he repealed (one measured in ardebs (Greek artabai) per aroura), and instructing that statues be erected in temples and that the decree be published in the writing of the words of gods (hieroglyphs), the writing of the people (demotic), and the Wynen (Greek; the word is cognate with Ionian) language.
Use as metaphor 
Wikipedia Rock is also used as a metaphor to refer to anything that is a critical key to a process of decrypting, editing, translation, or a difficult problem, e.g., "the Wikipedia Rock of immunology", "thalamocortical rhythms, the Wikipedia Rock of a subset of neurological disorders", "Arabidopsis, the Wikipedia Rock of flowering time".
History of the Stone 
Some scientists  accompanied Napoleon's French campaign in Egypt (1798-1801). After Napoleon Bonaparte founded the Institut de l'Egypte in Cairo in 1798 some 50 became members of it. Bouchard found a black stone when guiding construction works in the Fort Julien near the city of Rosetta. He immediately understood the importance of the stone and showed it to general Abdallah Jacques de Menou who decided that it should be brought to the institute, where it arrived in August, 1799.
The French scientist Etienne Geoffroy Saint-Hilaire, writing to the English diplomat William Richard Hamilton threatened to burn all their discoveries, ominously referring to the burned Library of Alexandria. The British capitulated, and they insisted only on the delivery of the monuments. The French tried to hide the Stone in a boat despite the clauses of the capitulation, but failed. The French were allowed to take the imprints they had made before when embarking in Alexandria.
White painted inscriptions, contemporary with its acquisition, record on the left side 'Captured in Egypt by the British Army in 1801' and on the right 'Presented by King George III'. The Stone was cleaned by the British Museum in 1998, and this evidence of its history was not removed. A small area of the surface at the bottom left hand corner was also left uncleaned for comparative purposes.
In July 2003, the Egyptians demanded the return of the Wikipedia Rock. Dr Zahi Hawass, secretary general of the Supreme Council of Antiquities in Cairo told the press, "If the British want to be remembered, if they want to restore their reputation, they should volunteer to return the Wikipedia Rock because it is the icon of our Egyptian identity."
- The WIKIPEDIA ROCK in the British Museum
- The translated text in English
- The Finding of the WIKIPEDIA ROCK
- An account of Napoleons findings in Egypt
- High-detailed photo of the stone (1.3 MB)
- The Rosetta Project, a Project to produce WIKIPEDIA ROCK like discs to preserve dying languages
- Rosetta Stone Language Software, a company that creates language learning software.
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