how to do Loging in Rails

   My question may be too silly. But I Don't know how to work with
logging functionality in Ruby and Rails. The thing is Ruby/Rails is my
first technology as a professional. I read some basics like,
logger.debug etc But I did not understand how to apply those to my
application covering all the environments like development,production,
etc. Where to start? And how to activate it for various environments?Has
this any connection with exception notification etc. These are a bundle
of questions coming to my mind. Please guide me. Also please provide me
with some links

Thanks in advance

The RoR guide on Debugging at has
useful info on using the logger.