Every domain name which is registered and hosted has lots of DNS records - some of them are set up automatically when you host a domain, others can be set up manually if necessary. For example, the A record of a domain name is its IP address i.e. this record reveals where the web site is situated; the MX records reveal where the e-mails are handled, while through an SRV record you can use a domain address for unconventional purposes, including a Voice-over-IP service. Being able to set up and modify particular records allows you to have different services with different providers if, for illustration, your present host provides dependable web hosting, but has difficulties with the email service, or you simply prefer to get a particular service from a particular company. Although you should be able to set up and edit these records freely and with no limits as you own a given domain, some companies charge extra to give you this option.