WEBVTT

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Opening a website feels like one action. Underneath it, several stages have to

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work. Separating those stages helps you explain what succeeded and what failed.

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First, a name lookup can return an address record. That gives the client

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information about a destination. It does not prove that the website is listening

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or that the page will work.

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Next, the client tries to connect. A protected connection also involves checking

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the server identity and agreeing how to protect the exchange. A DNS success does

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not guarantee connection success.

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HTTP carries a request and a response. The response has a status, headers, and

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often a body. The document might succeed while a stylesheet, an image, or a

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script fails.

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The browser puts those resources together. A useful test checks more than the

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first response. It checks whether the page can be read, whether resources load,

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and whether the intended interaction works.

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Try this question. A name resolves, but a connection is refused. Which stage

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needs your attention next? Start with the connection, not an assumption that DNS

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must be wrong. Continue with the learning path to practice.