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Frontend Glossary

Frontend engineering · Performance

Cache

Also called: HTTP cache, In-memory cache, Cache-Control

Temporarily store computed or fetched results for reuse—browser cache, CDN, server memory/Redis, or in-app caches.

In detail

Caching speeds things up and also causes "I deployed but nothing changed." Browsers honor Cache-Control/ETag; CDNs cache static assets; APIs may cache hot reads.

Invalidation is the hard part: time-based expiry, version/hash keys, or explicit purge. Be careful caching personalized or auth-gated responses across users.

When debugging: private window, hard reload, and Network (from disk cache) show which layer is sticky.

Developer info
Term ID
eng-cache
DOM selectors
No DOM cues. This concept isn't detected directly on a page.
Priority
1 · when several match at the same level, the higher priority wins
Version
v1 · updated Oct 5, 2026