An SRV record, which signifies Service record, is a DNS entry that is used to define the servers which run a particular service for a domain. In other words, you can use your domain not just for a website, but also for an instant messaging server, a video streaming host or even a Voice-Over-IP server, for instance, while you still have a website with it. If you set up the SRV record, you can choose what Internet Protocol it's going to use, on which port the connection to the specific server is going to be established in addition to the priority and the weight of the record in case that you have several SRV records for the exact same service. The latter option will enable you to employ different machines for load balancing and redundancy. With this kind of DNS records, you may use the same domain address for various purposes and even with different companies if the same one can't provide all services you require.