Every single domain that 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 manually if required. As an example, the A record of a domain is its IP address i.e. this record reveals where the web site is situated; the MX records show where the emails are stored, while through an SRV record you can use a domain name for unconventional purposes, for instance a Voice-over-IP service. To be able to set up and modify particular records enables you to have different services with different companies if, for illustration, your present host provides dependable web hosting, but has problems with the e-mail service, or you simply prefer to get a particular service from a specific company. Although you can set up and edit these records freely and with no limitations as you own a given domain, a lot of companies charge extra to give you this option.