Wikipedia:Main Page history/2017 August 27
From today's featured articleLead is a chemical element with symbol Pb and atomic number 82. A heavy metal with a density exceeding that of most common materials, it is malleable and has a low melting point for a metal. Chemically, it is a relatively unreactive post-transition metal. Lead was known to prehistoric people. A principal ore of lead, galena, often bears silver; interest in silver sparked lead extraction and use in ancient Rome. Lead production declined after the fall of Rome and did not reach comparable levels until the Industrial Revolution. Nowadays, global production of lead is about ten million tonnes annually. Its high density, low melting point, high malleability, relative inertness to oxidation, relative abundance, and low cost have resulted in its extensive use in construction, plumbing, batteries, bullets and shot, weights, solders, pewters, fusible alloys, and radiation shielding. In the late 19th century, lead was recognized as highly toxic, and since then it has been phased out for many uses. A neurotoxin that accumulates in soft tissues and bones, it can damage the nervous system and cause brain and blood disorders. (Full article...)
Recently featured:
Did you know...
|
In the news
On this day...
Tomás Luis de Victoria (d. 1611) · Man Ray (b. 1890) · Brian Epstein (d. 1967) |
Today's featured picture
Gordon Tobing (1925–1993) was an Indonesian singer of folk songs, particularly those in the Batak language. Born to a Batak family in Medan, North Sumatra, Tobing moved to Jakarta in 1950 and began working in the entertainment industry. While with Radio Republik Indonesia, he participated in an Indonesian cultural mission to the 4th World Festival of Youth and Students. Over the remainder of his life Tobing was included in numerous similar missions, ultimately travelling to five continents and performing for President Suharto of Indonesia, Crown Prince Akihito of Japan, and other world leaders. Photograph: Tati Studios, Jakarta; restoration: Chris Woodrich |
Other areas of Wikipedia
- Community portal – Bulletin board, projects, resources and activities covering a wide range of Wikipedia areas.
- Help desk – Ask questions about using Wikipedia.
- Local embassy – For Wikipedia-related communication in languages other than English.
- Reference desk – Serving as virtual librarians, Wikipedia volunteers tackle your questions on a wide range of subjects.
- Site news – Announcements, updates, articles and press releases on Wikipedia and the Wikimedia Foundation.
- Village pump – For discussions about Wikipedia itself, including areas for technical issues and policies.
Wikipedia's sister projects
Wikipedia is hosted by the Wikimedia Foundation, a non-profit organization that also hosts a range of other projects:
Commons Free media repository |
MediaWiki Wiki software development |
Meta-Wiki Wikimedia project coordination |
|||
Wikibooks Free textbooks and manuals |
Wikidata Free knowledge base |
Wikinews Free-content news |
|||
Wikiquote Collection of quotations |
Wikisource Free-content library |
Wikispecies Directory of species |
|||
Wikiversity Free learning materials and activities |
Wikivoyage Free travel guide |
Wiktionary Dictionary and thesaurus |