Any time you add a domain name as hosted in some account, you typically set a pair of Name Servers to direct it to that particular provider. On their end, three records are set up automatically when the domain address is added - one A record and two MX records. The first one is a numeric address, or IP address, which “tells” the domain name where its website is, while the other two are alphanumeric and they reveal the server that deals with the e-mails for that particular Internet domain. The site and the email hosting are generally regarded as one thing, when they are actually two different services. Having independent records for them will enable you to have them with different providers if you want. As an illustration, some new company might have excellent uptime for your website, but you might not want to switch your e-mails from your current host and by using an A record to point the domain address to the first and MX records to have the e-mails with the second, you can get the best of both providers. These records are checked when you want to open a website or send an email - either way, the provider whose name servers are used for the Internet domain will be contacted to retrieve the A and MX records and if you've set records different from their own, the right web/mail server will then be contacted and you're going to see the needed site or your e-mail will be delivered.