Every registered domain has no less than two Name Server records that show where it is hosted i.e. by using these records you direct your Internet domain to the servers of a specific website hosting company. That way, you have got both your website and your e-mails managed by the same company. On the lower level of the Domain Name System (DNS), however, there is a variety of other records, for instance A and MX. The former shows which server manages the website for a given domain and is always an IP address (123.123.123.123), while the latter reveals which server deals with the e-mails and is always an alphanumeric string (mx1.domain.com). As an illustration, whenever you enter a domain name in your Internet browser, your request is forwarded through the global DNS system to the company whose NS records the domain address uses and from there you could be sent to the servers of another provider provided you have set an IP address of the latter as an A record for your domain name. Having separate records for the site and the emails means that you can have your website and your emails with two different providers if you wish.