juniorCaching

What is Caching?

Updated Apr 28, 2026

Short answer

Caching is the process of storing copies of data in a high-speed storage layer to serve future requests faster.

Deep explanation

Caching is essential for performance optimization. Caching is the process of storing copies of data in a high-speed storage layer to serve future requests faster. By reducing the need to access slower storage layers (like HDDs or remote databases), systems can achieve much lower latency.

Real-world example

Storing the results of a complex database query in Redis.

Common mistakes

  • Not setting a TTL, leading to the cache growing indefinitely or serving very old data.

Follow-up questions

  • Is cache persistent?

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