Quick definition · 2 min Internet & web term

404 error

A 404 error means the web page or address you asked for does not exist or could not be found.

Think of it like

Knocking on an apartment that is empty, or has the wrong number. Nobody is there to answer.

Example

A fresh deploy often shows a 404 because a link points somewhere that was not built yet. The number 404 just means “not found.”

Why it matters

It is the most common error a new live site throws, and the bare number tells a beginner nothing on its own.

Where you’ll see it
every websitefresh deploys
Go deeper What status codes mean: HTTP explained → The full explainer. This quick definition is just the on-ramp. Next step Status codes explained: HTTP → What 404, 200, and 500 actually mean.
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