FrontendHaltPerformance·Intermediate·Conceptual·1 min read
How do content-hashed filenames help image performance?
Short interview answer
They let the CDN and browser cache an image effectively forever, since a changed image gets a new filename and thus a new cache entry. Without them you're stuck choosing between short cache lifetimes and users seeing stale images after an update.
Key takeaway
Explain the underlying mental model clearly, then support it with a concrete example and its trade-offs.