NickServ

ZEnet's nick registration service allows users to register a nickname by providing a password, preventing other users from using it. NickServ registration is required for such things as registering channels and sending/receiving memos.

MemoServ

MemoServ allows users to send memos to other users with registered nicks even when they are offline.
Memos can be sent to individual users or to all ops in a specific channel.

HostServ

HostServ is a servces bot as makes it possible for all registerd users to request thier own (hidden hostname, ex: my.name.is.this) this function is very good to use when you dont want other peoples to found out your real ip/hostname address.

ChanServ

ZEnet's channel registration service, supplies users with a way to secure their channels from takeovers. Founding a channel gives a user the right to add and remove ops and akicks, lock channel modes, etc.

BotServ

With BotServ can you request a services bot from the botlist as will join your registerd channel, the bot has a few functions as might be useful in many ways .
You can also make the services bot to be like a "normal" bot with channel commands and much other stuffs.