Each and every 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 created manually if required. For example, the A record of a domain is its IP address i.e. this record shows where the web site is situated; the MX records show where the e-mails are managed, while with an SRV record you can use a domain for unconventional purposes, like a Voice-over-IP service. The ability to create and modify certain records permits you to have different services with different companies if, for instance, your present host provides dependable web hosting, but has problems with the email service, or you simply prefer to get a particular service from a certain company. While you must be able to set up and edit these records freely and with no restrictions as you own a given domain, lots of companies charge extra to give you this option.