It's based on a network of satellites that circle the Earth, bombarding it with signals.

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You need a classy pie chart, or a 3D graphic of a software-stack or one of those social network symbols with a circle and branches coming out of it.

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The northernmost Geopark of the network, not far from the Arctic Circle, is a unique combination of northern hemisphere geology, nature and culture.

UNESCO: NATURAL SCIENCES

Examples of these groups include Investors' Circle in San Francisco, Hyde Park Angel Network in Chicago and Golden Seeds in New York.

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If your network connection is not consistent, you may experience problems connecting - the video will pause and a circle will spin on your screen.

BBC: Your guide to the BBC Embedded Media Player