MODE <nick> <+|-><modes>

User modes: (* designates that the umode is oper only)

     USER MODE    DESCRIPTION
-----------------------------------------------------------------
       * o     - Designates this client is an IRC Operator.
                 Use the OPER command to attain this.
         i     - Designates this client 'invisible'.
         w     - Can see server wallops.
         W     - User is connected using a webirc gateway.
       * l     - Can see oper locops (local wallops).
       * c     - Can see client connections and exits.
       * u     - Can see unauthorized client connections.
       * j     - Can see 'rejected' client notices.
       * k     - Can see server kill messages.
       * f     - Can see 'auth {} block is full' notices.
       * F     - Can see remote client connection/quit notices.
       * y     - Can see stats/links/admin requests to name a few.
       * d     - Can see server debug messages.
       * n     - Can see client nick changes.
         p     - Hides channel list in WHOIS.
         q     - Hides idle and signon time in WHOIS.
         r     - User has been registered and identified for its nick.
                 Can be set only by servers and services.
         R     - Only registered clients may message you.
         s     - Can see generic server messages and oper kills.
         S     - Client is connected via SSL/TLS.
       * e     - Can see new server introduction and split messages.
       * b     - Can see possible bot/join flood warnings.
       * a     - Is marked as a server admin in stats o/p.
         D     - "Deaf": don't receive channel messages.
         G     - "Soft Caller ID": block private messages from people not on
                 any common channels with you (unless they are accepted).
         g     - "Caller ID" mode: only allow accepted clients to message you.
       * H     - IRC operator status is hidden to other users.
