DNS—the Domain Name System—connects human-readable names such as a website’s domain to records that computers use, including IP addresses. It helps your device find where to connect when you open a site by name.
The name and the page are different things
MDN describes DNS as a hierarchical, decentralized naming system. Looking up a name is a different operation from downloading the page found at that address.
Imagine a friend says a new café has moved. Finding its current address and ordering a coffee are separate tasks. That analogy helps separate a lookup problem from a problem with the destination itself; it is not a literal description of the network.
Who answers the lookup?
According to Cloudflare’s DNS explanation, a recursive resolver looks for the requested record. If it does not already have a usable cached answer, it can follow the naming hierarchy toward an authoritative nameserver, which holds the relevant records.
Caching avoids doing the full lookup from scratch every time. A stored answer can remain available for its allowed lifetime. This is one reason a change made by a site owner may not be reflected immediately in every lookup.
What an error does—and does not—tell you
If a browser reports a name-lookup problem, that is a clue about one step in opening the site. It is not, on its own, proof that the article was deleted or that the site has permanently closed.
For a useful report to a site owner, copy the exact address and error message. Note whether the problem affects only that name or several unrelated sites. Avoid changing several network settings at once: if something improves, you will otherwise have little idea which change mattered.
Consider this imaginary report: “The homepage name will not resolve on my laptop, but another site opens.” That gives someone investigating the issue a much better starting point than “the internet is down.”
Once the address has been found, another system can reuse page resources. That is the job discussed in our browser-cache explainer. Or explore the web beyond your usual feed.
