Logging in the Code and out
1. Why Logs?
Logs are a way to log what's going on in your application. Logs show up in the console or in log files on disk. See history of the term.
2. Logging Levels
3. How to write a useful log message
All log messages should be:
Specific -- easy to pinpoint where
Meaningful -- provide discerning information to identify what's wrong & some context
Actionable -- provide information with which to attempt to fix the problem or further debug / recreate
Relevant -- provide information pertinent to the situation, not redundant or superfluous
Terse -- Get to the point and be clear about it