Studio1337 resellers have the ability to set up their own nameservers. This means they can issue the server names used to point DNS from the registrar to our hardware.
For example, let's say Reseller XYZ owns the domain "ResellerXYZ.com". He or she can create new nameservers (NS1.RESELLERXYZ.COM and NS2.RESELLERXYZ.COM) and use those with hosting customers, instead of using the default Studio1337 nameservers.
Studio1337 supplies generic nameservers as well, should you not wish to register your own names.