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Computing History & Legendary BugsSoftware Bugs

The Leap Second That Crashed Websites

In 2012 one extra second took down popular sites

Have you ever seen a clock show 23:59:60? In 2012 computers did, and some big websites fell over. Why would one second matter?

You'll find out

  • Why the world adds a second
  • What a 61-second minute broke
  • How some companies hide the second

Why it matters

Every app trusts its clock. Odd moments in time still trip real software, and knowing them helps you spot the bugs.

About 3 min6 interactive slides · 5 questionsLesson 247 · Zone 28

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