DNS is the service that translates 'human' addresses like into 'computer' IP addresses like 74. 125. 67. 100. DNS errors occur when the server cannot find the translation.
DNS stands for domain name server, which are computers that route traffic to other computers on the Internet. Errors happen when a computer cannot be found by the DNS.
DNS or (Domain Name Server) is part of the protocol that allows you to link to the net and other pc's (LAN etc. ). There are a plethora of DNS errors that could occur. If you want advice on how to resolve the issue provide further information.