One of the worst nightmares any database professional can have if they get a call reporting their production database is corrupted and user operations can not continue. Although there are so many good resources available over the internet on this subject, recently I found an extremely useful blog entry from
PSS Escalation engineers on this subject. I strongly encourage everyone to refer to this post to be well prepared to handle such situation.
If you are already experiencing a situation where corruption is impacting your users, best bet is to initiate your DR or recover from last known good backup to be back to business immediately (Unless you decide to keep the corrupted database online and to do a recovery on highest priority) before you resolve the root cause of the corruption.
Here is a collection of common errors you may face due to various corruptions with resolutions recommended from Microsoft:
Hopefully this post is a good point of start to learn how to fix corruption or to fire-fight a situation to resolve a database corruption issue.