FrontendHaltNetworking·Intermediate·Conceptual·1 min read
How do preconnect and preload differ?
Short interview answer
preconnect performs the DNS, TCP, and TLS setup to an origin ahead of need, so the first request there is faster. preload actually fetches a specific resource now at high priority, for something the browser wouldn't discover early otherwise, like a font referenced deep in CSS.
Key takeaway
Explain the underlying mental model clearly, then support it with a concrete example and its trade-offs.