Glossary

Caching

Keeping a copy of expensive-to-fetch data somewhere faster (memory, CDN) to cut latency and load.

1 min read·4 sections
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Definition

Keeping a copy of expensive-to-fetch data somewhere faster (memory, CDN) to cut latency and load.

How it works

The biggest single lever for read-heavy systems. Layers stack: browser → CDN → app/Redis → database. The hard parts are invalidation (keeping the copy fresh) and the cold-cache stampede. Set TTLs, choose a strategy (cache-aside, write-through), and decide what staleness you can tolerate.

Common questions

What is Caching?

Keeping a copy of expensive-to-fetch data somewhere faster (memory, CDN) to cut latency and load.

How does Caching work?

The biggest single lever for read-heavy systems. Layers stack: browser → CDN → app/Redis → database. The hard parts are invalidation (keeping the copy fresh) and the cold-cache stampede. Set TTLs, choose a strategy (cache-aside, write-through), and decide what staleness you can…

What is Caching used for in system design?

The biggest single lever for read-heavy systems. Layers stack: browser → CDN → app/Redis → database. The hard parts are invalidation (keeping the copy fresh) and the cold-cache stampede. Set TTLs, choose a strategy (cache-aside, write-through), and decide what staleness you can…

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