Every domain name that is registered and hosted has a great deal of DNS records - some of them are created automatically when you host a domain, others can be created manually if required. For instance, the A record of a domain address is its IP address i.e. this record shows where the site is situated; the MX records reveal where the e-mails are managed, while through an SRV record you can use a domain address for unconventional purposes, including a Voice-over-IP service. The ability to create and modify certain records allows you to have different services with different companies if, for example, your present host provides dependable web hosting, but has problems with the email service, or you simply prefer to get a certain service from a particular company. Even though you must be able to set up and modify these records freely and without any restrictions as you own a given domain name, a lot of companies charge extra to give you this option.