There are several different access levels. They are represented by single letter flags. In order they are:
ADD - Adds the specified Flag
DEL - Deletes the specified Flag
LIST - Lists all Operator Flags.
Flag - Level
a - Server Administrator
c - Configuration Access
d - Disabled Operator
e - Require Encrypted
g - Global Operator
h - Helper
s - Services Administrator
If none of these flags are used the operator will be defined as a local operator. The h flag allows the person to see HelpOps and be marked as helpful. Giving someone the c flag gives access to the web based and online configurations. Configuration access should be reserved for only the most trusted personnel.
/as help oper flag <topic>
To see the abilities given to different flags see the OperServ and AdminServ sections of the Command Reference.