Google's Spanner database is designed to operate seamlessly between data centers around the world, keeping data synchronized across time and distance. To manage the global database and keep it running smoothly, the company had to invent its own reliable way of keeping time consistent between its servers. To accomplish this task, Google created the TrueTime API, a system that uses atomic clocks and GPS receivers in each Spanner data center to keep time consistent between its servers. Head over to Wired for the full story on Spanner from Google's engineers.