Facebook chief executive Mark Zuckerberg introduced the new "Graph Search" feature at a press event in California.
He said: "Every piece of content has its own audience; most content is not public; you can only search for content that has been shared with you".
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A fine evening ahead to the south with some late sunshine in places.
Prince Charles and the Duchess of Cornwall have visited Manchester Arena, the site of a suicide bombing in May which left 22 people dead.
Flammable cladding has been found on 75 high-rise buildings across 26 local authority areas, MPs have been told.