(1) System Messages
(2) Instructional Messages

(1) System Message
      System Messages are generated by the system to keep the user informed of the system’s state and activities.
      System Messages are further classified into

(i) Status Messages
(ii) Information Messages (Notification Messages)
(iii) Warning Messages
(iv) Critical Messages
(v) Question Messages

(i) Status Messages
     Status Messages provides the information about the progress of any operation.

(ii) Information Messages (Notification Messages)
      Information Messages gives us information or notify us about the operation which was being executing.

(iii) Warning Messages
      The user must determine whether the situation is in fact a problem and may be asked to advise the system whether or not to proceed. (A deletion request by a user is any action that commonly generates a warning message.

(iv) Critical Messages
      Critical Messages call attention to conditions that require a user action before the system can proceed.

(v) Question Messages
      A question message asks a question and offers a choice of option for selection.

(2) Instructional Messages
      Instruction Messages provide Instruction at the depth of details to user so they can use the system without any problem.
      In writing, Manual must be provided to user.