• Describe the design approach to the class
• Describe limitations, usage assumptions, and so on
• Comment the class interface, can someone easily understand how to use the class without actually looking at the implementation
• Don't document implementation details in the class interface

   Here is an example:

   /*-------------------------------------
     Class Declarations
   -------------------------------------*/

   /*-------------------------------------------------------
     Class:  PerfTimer
     Desc:   Simple Performance Timer
     Notes:   
       1. Wrapper around WIN32 QueryPerformanceCounter() 
          API function.
     Usage:
       Create PerfTimer variable 
       wrap code to be timed with calls to start()/stop()
       call Dump() to display results to user.
   -------------------------------------------------------*/


-- Main.ShawnDB - 16 Jun 2008