The server log records information about events such as the startup and shutdown of servers,the deployment of new applications, or the failure of one or more subsystems. The messages include information about the time and date of the event as well as the ID of the user who initiated the event. Standard output logs
In addition to writing messages to a log file, each server instance prints a subset of its messages to standard out. Usually, standard out is the shell (command prompt) in which you are running the server instance.WebLogic Server administrators and developers configure logging output and filter log messages to troubleshoot errors or to receive notification for specific events.