Loggers provide a capability to view the internal runtime workings of UrlRewriter.NET. If you want to see the rewriting rules firing (or not!), then you can register a logger and view the messages. By default, no logging is enabled for maximum performance.

Debug Logger
provides a simple way to get the messages to the standard Debug output.
Create your own custom logger
you can easily extend the component by implementing your own logger or wrapping a logging framework like log4net or the Enterprise Library.