The time is incredibly important to organize our daily life. We need that time to get up for work when, on the bus, and even go to sleep to make sure that we know enough Shut Eye.
Generally speaking, for this kind of timing or mechanical digital watches provide us with much accuracy. A digital clock is likely to lose more than a second over the space of one week, and I'm sure your boss will not mind if you arrive late for your shift for a second.
However, if itcomes to transmitting data over the Internet, controlling satellites, or even the acquisition of shares on the stock market a more accurate timing is not required.
Computer networks rely on timekeeping for nearly all applications, from sending an email to saving data, a time stamp is required for computers to keep on track. Even routers and switches, all running at the same speed, out of sync devices can lose data and even entire connections.
For satellite navigation, on long -by ships and companies, but increasingly in modern cars, accuracy of one millisecond, one thousandth of a second) (It is important, as the light (and can) so that radio waves travel 300 km in this period, so that any small error in the time signal would mean, satellite navigation could be inaccurate by hundreds of miles.
Computers need not only require in order to synchronize their network, but time sensitive transactions with other networks, computers or the Internet alsoSynchronization. Make you recognize yourself bidding on eBay and placing the last bid for the auction computer with a different date to an earlier bidder as the last one, you'd probably be offended.
For this reason, a standard global time scale is used to allow all the computers around the world to sync at the exact same time source. These global scale is as UTC (Universal Coordinated Time).
UTC time is based on International Atomic Time (TAI), with which aTime, as I said,) by an international group of atomic clocks (260 in 40 different laboratories around the world, where the average is taken, which means that TAI with an accuracy of one second every three million years ago.
UTC time leap second is added (or taken away) every year or so to the slow (and occasionally compensate for the acceleration) of the rotation of the planet Earth actually 100,000 times less reliable than an atomic clock and no leap seconds Clockwould end at midnight (though in 40,000 years or so).
Computers use a protocol called NTP (Network Time Protocol), the UTC time a signal is received either over the Internet or via a specialist radio transmission from a physics lab or via the GPS network.
NTP server then make sure that all devices are connected to the UTC synchronized network allows computers around the world to communicate effectively with each other.
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