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What does "uptime" mean in programming?
uptime is one of the most common terms in software development. This guide explains what it means, how it is used in practice, and why it matters, with real examples from the developer world.
Definition
The percentage of time a system is operational and accessible to users. Expressed as a percentage: 99.9% uptime means the system is down for at most 8.7 hours per year. The difference between 99.9% and 99.99% is significant: 99.99% allows only 52 minutes of downtime per year.
Example
"We had 99.95% uptime last quarter — two incidents brought us below our 99.99% target."
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