I think there are a few fundamentals about logs that you don't understand very well right now.
Originally Posted by balteo
I am sitting in front of the logs viewer application trying to understand the different categories of logs available.
A "log viewer" would be a different thing. What you are investigating are simply the system logs, which are usually stored into /var/log/ by your system logger
The system logger is a daemon, a program that loads at boot time and sits on the background. Some programs ask this logger to save some info that could be useful at later stages, for diagnosis or for other purposes. That info goes into /var/logs/, the concrete file name and place depends only on the concrete system logger that you use and its configuration.
There are some common names for logs, but bear in mind that that's just the convention
, and not something that's carved in stone. They can differ from logger to logger and from system to system.
Here is what I understand and what I don't understand:
Xorg.0.log: all that's related to the X server messages??
Xorg.N.log, being 'n' a number, is the log for the Xorg session running on the 'n'th display. Hence, Xorg.0.log is the log for the display number zero. If you run many X session and / or your computer serves remote sessions, and / or you have multiple displays on a non-xinerama/xrandr (or similar mode) then you can have many sessions with different $DISPLAY numbers on the same computer.
This is a register of the logins. Users that log into and out of the system.
Presumably log about the daemons that load and unload, not sure if it will hold something else.
kern.log: all the messages related to kernel and device drivers??
These are a bit fuzzy, what does into each file will be clearer if you take a look at the config of your system logger. You first need to know what your logger is. Common ones are syslog-ng, ksyslogd or metalog.