0 below link helpful..:)
http://www.dotnet-guide.com/what-is-the-difference-between-trace-and-debug-in-dot-net.html
0 Did you meant the classes available in C#. If so, as per MSDN:
Debug class:
Provides a set of methods and properties that help debug your code.
Trace class:
Provides a set of methods and properties that help you trace the execution of your code.
Hope this helps!