The master name server should be the main name server in the local network. It has the top authority in all other name servers.

Slave name servers sometime act as a secondary name server. One local network or WAN can have more than one slave name server. It has less control than Master name server but more control than forward and caching name servers.

Cache name server dose not have much power in the network. It basically update the table instead. It is widely used in small subnet to obtain better performance.

Fowarding server dose not store any record. It would be useful in a big network.