Any active domain name that is added in a hosting account has a variety of records which allow it to perform properly. In the typical case, the name servers (NS records) show the location where the Internet domain is hosted and they are set on the side of the registrar company, but on the lower level there are specific records set through the hosting company such as A (IP address of the website/server), MX (email server), SRV (using a domain address for non-website purposes on a particular port number such as Voice-over-IP), etc. By having access to these records and by being able to edit them, you may have your website with company A and your e-mail messages with company B, for instance. This offers you more freedom since you can pick the best provider for every one of these services and you do not have to stick with a single company. Whenever you choose a hosting company, you have to make sure that you can access all DNS records freely since some companies have an additional fee for this feature.