text: The venture's backers include Tesla Motors and SpaceX CEO Elon Musk, Paypal co-founder Peter Thiel, Indian tech giant Infosys and Amazon Web Services.
  Open AI says it expects its research - free from financial obligations - to focus on a "positive human impact".
  Scientists have warned that advances in AI could ultimately threaten humanity.
  Mr Musk recently told students at the Massachusetts Institute of Technology (MIT) that AI was humanity's "biggest existential threat".
  Last year, British theoretical physicist Stephen Hawking told the BBC AI could potentially "re-design itself at an ever increasing rate", superseding humans by outpacing biological evolution.
  However, other experts have argued that the risk of AI posing any threat to humans remains remote.
  A statement on OpenAI's website said the venture aims "to advance digital intelligence in the way that is most likely to benefit humanity as a whole, unconstrained by a need to generate financial return".
  "It's hard to fathom how much human-level AI could benefit society, and it's equally hard to imagine how much it could damage society if built or used incorrectly."
  The statement said AI "should be an extension of individual human wills and, in the spirit of liberty, as broadly and evenly distributed as is possible safely".
  It said only a tiny fraction of the $1bn pledged would be spent in the next few years.
target: Prominent tech executives have pledged $1bn (£659m) for OpenAI, a non-profit venture that aims to develop artificial intelligence (AI) to benefit humanity.