FrontendHaltNetworking·Intermediate·Conceptual·1 min read
What is the difference between freshness and validation?
Short interview answer
A fresh cached response can be reused without contacting the origin. A stale response may be conditionally revalidated with an ETag or Last-Modified validator; a 304 confirms the stored representation remains usable.
Key takeaway
Explain the underlying mental model clearly, then support it with a concrete example and its trade-offs.