What is caching?

Updated May 17, 2026

Short answer

Caching stores frequently used data for faster access.

Deep explanation

It reduces repeated computations or database calls by storing results in fast storage like memory.

Real-world example

Browser caching images for faster page loads.

Common mistakes

  • Not invalidating stale cache data.

Follow-up questions

  • What is cache invalidation?
  • Where is caching used?

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