What is Proto-Indo-European language?
{{for|the hypothetical speakers of this language|Proto-Indo-Europeans}} [[File:IE1500BP.png|thumb|300px|Indo-European languages around 500 [[AD]]]] The '''Proto-Indo-European language''' ('''PIE''') is the ancestor of the [[Indo-European languages]].<ref>Mallory J.P. & Adams D.Q. 2006. ''The Oxford introduction to Proto-Indo-European and the Proto-Indo-European world''. Oxford: Oxford University Press. {{ISBN|0-19-929668-5}}</ref> It is the best understood of all [[proto-language]]s.<ref>Ivanov, Vyacheslav V.& Gamkrelidze, Thomas 1990. The early history of Indo-­European languages. ''Scientific American'' '''262''', March.</ref> It was put together by the methods of [[historical linguistics]].<ref>Beekes Robert 1995. ''Comparative Indo-European linguistics: an introduction''. Amsterdam: John Benjamins. {{ISBN|90-272-2150-2}} (Europe), {{ISBN|1-55619-504-4}} (US)</ref> == Discovery and reconstruction == There are different [[hypotheses|theories]] concerning when and where PIE was spoken.<ref>{{Cite web |url=http://www.psych.auckland.ac.nz/Psych/research/Evolution/Gray%26Atkinson2003.pdf |title=Russell D. Gray and Quentin D. Atkinson, Language-tree divergence times support the Anatolian theory of Indo-European origin, Nature 426 (27 November 2003) 435-439 |access-date=14 June 2007 |archive-date=2 April 2007 |archive-url=https://web.archive.org/web/20070402070222/http://www.psych.auckland.ac.nz/Psych/research/Evolution/Gray%26Atkinson2003.pdf |url-status=dead }}</ref> PIE may have been spoken as a single language. Then it began to separate, around 3700 [[BC]]. The exact date is not known. The most popular hypothesis for where it came from and how it spread is called the [[Kurgan hypothesis]]. In this theory, its origin is in the Pontic-Caspian [[steppe]] of Eastern Europe. === Method === There is no direct evidence of PIE because it was never [[written language|written down]]. All PIE sounds and words are reconstructed from later Indo-European languages. The [[asterisk]] symbol is used to mark reconstructed PIE w