What are redo log files doing

I'm new to the oracle and trying to understand functionality of redo logs. So can someone put information about redo logs and how to recover using redo logs?
regards
chanaka

843833 wrote:
I'm new to the oracle and trying to understand functionality of redo logs. So can someone put information about redo logs and how to recover using redo logs?
regards
chanaka
Overview of the Online Redo Log
http://download.oracle.com/docs/cd/E11882_01/server.112/e16508/physical.htm#CNCPT11302
Oracle is going to use them to do the roll forward which means to reapply the changes over the blocks after, for example, a crashed instance restarts.
HTH
Aman....

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