Whenever you add a domain as hosted in some account, you usually set a pair of Name Servers to direct it to that particular service provider. On their end, 3 records are set up automatically when the domain name is added - one A record and two MX records. The first one is a numeric address, or IP address, that “tells” the Internet domain where its website is, while the other two are alphanumeric and they reveal the server that deals with the emails for that specific domain name. The website and the email hosting are generally considered to be one thing, while they are actually two different services. Having independent records for them will permit you to have them with different providers if you want. As an illustration, some new provider can have fantastic uptime for your website, but you may not want to switch your e-mail messages from your current host and by using an A record to point the domain to the former and MX records to have the e-mails with the latter, you could get the best of both companies. These records are checked whenever you want to open a website or send an email - in any case, the company whose name servers are used for the Internet domain will be contacted to retrieve the A and MX records and if you have set records different from their own, the correct web/mail server will then be contacted and you are going to see the needed website or your email will be delivered.