Every computer on the network has to register the DNS Records in the DNS Server so that a computer can be accessed by name also. The DNS Query will always go to DNS Server for resolving Name to IP and vice-versa.
The following services are responsible to register (A) Host Record and PTR Records when the client computers start:
DHCP Client Service
A computer running Windows XP, Windows 2000, Windows 2003 use DHCP client service to register Host and PTR Records in the DNS Server.
DNS Client Service
A computer running Windows Vista, Windows 7 and Windows Server 2008 always use DNS Client service to register Host and PTR Records in the DNS Server. Computers running these version of windows do not use DHCP Client Service.