My mind doesn't understand how they work. I just use them.How does my Sat Nav know I've made an unscheduled turn off the M18 to avoid miles of tailback, then tell me how to get back on further up and miss the traffic?
"How does my Sat Nav know I've made an unscheduled turn off the M18 to avoid miles of tailback"
Something called a GPS. They also have "Maps" downloaded, so they know which roads to use and what they're called, and they use this info with your "GPS location".
Of course I know the theory. But I am one of millions of users of GPS yet I can be personally found from outa space and this intelligence can divert me to the correct route in literally seconds. That to me is magic.