In 1977 or thereabouts a collection of scientists huddled around a secret radio receiver in the US desert. This was the start of GPS, Glonass, Gallileo and the whole navigation industry. A GPS chipset now costs, in bulk, a few dollars so your watch, your phone, your computer all have GPS receivers and everyone knows where they are all the time. But how does this technology work? And are there situations when it does not work? A lecture by Richard Harvey The transcript and downloadable versions of the lecture are available from the Gresham College website: https://www.gresham.ac.uk/lectures-and-events/gps Gresham College has offered free public lectures for over 400 years, thanks to the generosity of our supporters. There are currently over 2,500 lectures free to access. We believe that everyone should have the opportunity to learn from some of the greatest minds. To support Gresham's mission, please consider making a donation: https://gresham.ac.uk/support/ Website: https://gresham.ac.uk/ Twitter: https://twitter.com/greshamcollege Facebook: https://facebook.com/greshamcollege Instagram: https://instagram.com/greshamcollege