Observer Apex : Observer Apex : Reacting to network events : Understanding logging in Apex
Understanding logging in Apex
Logging captures events that occur in the application and between assets. These events may range from informational to critical.
Logging creates an audit trail, or transaction log, allowing you as an administrator to see who did what and when they did it. You may need this information for compliance or other reasons.
Another reason logging can be useful is if you have a problem with the application, the log events will help identify where the issue is occurring.