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 created by hand if needed. As an illustration, the A record of a domain address is its IP address i.e. this record shows where the site is located; the MX records reveal where the e-mails are managed, while with an SRV record you can use a domain name for unconventional purposes, such as a Voice-over-IP service. Being able to set up and modify specific records allows you to have different services with different providers if, for instance, your current host provides dependable web hosting, but has difficulties with the e-mail service, or you simply prefer to get a certain service from a specific company. Though you must be able to set up and modify these records freely and with no restrictions as you own a given domain, a lot of companies charge extra to give you this option.