What does DNS could not resolve the host name mean?

I can't login to SL it says DNS could not resolve the host name.

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Answer:
The DNS converts a web name to a numeric IP address.

If you are unable to get any web sites to display you have a router configuration or network configuration problem you need to address. This can be a rather lengthy process and beyond the scope of your question.

If you are able to get web pages except for one, then the problem is with the site you wish to see. They may have changed hosting and the servers need to catch up with this change - which can take up to 48 hours. In this case I would wait for the 48 hours.

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Answer:
whats SL? lol that means that ur primary DNS server and alternative DNS server do not have a resolution for the domain name u are looking for,, it can be because u are mistyping it or because it doesn't exist lastly because the domain doesn't have global distribution u can use the nslookup command to see if other DNS servers have an entry or u can determine if the name is correct

hints:

nslookup example.com 4.2.2.2

see if veriZon public has an entry for it