What is Load Balancing?

Updated Apr 28, 2026

Short answer

Distributing incoming traffic across multiple servers to prevent overload and ensure availability.

Deep explanation

Availability and Reliability are the cornerstones of production-grade systems. Distributing incoming traffic across multiple servers to prevent overload and ensure availability. Ensuring high uptime requires both preventing failures and minimizing recovery time.

Real-world example

A website staying up during a traffic spike by using multiple servers.

Common mistakes

  • Assuming a system is reliable just because it is available (e.g., it's 'up' but returns errors).

Follow-up questions

  • How many minutes of downtime is 99.99% availability?

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