Each and every domain name which is registered and hosted has a great deal of DNS records - some of them are set up automatically when you host a domain, others can be set up by hand if necessary. As an illustration, the A record of a domain address is its IP address i.e. this record reveals where the web site is situated; the MX records reveal where the e-mails are stored, while with an SRV record you can use a domain address for unconventional purposes, like a Voice-over-IP service. To be able to create and modify particular records permits you to have different services with different companies if, for instance, your present host provides stable web hosting, but has difficulties with the e-mail service, or you simply prefer to get a specific service from a certain company. While you will be able to set up and edit these records freely and with no restrictions as you own a given domain name, some companies charge extra to give you this option.