Console creates a visualization for messages logged through calls to a YUI instance's Y.log( message, category, source ) method. The debug versions of YUI modules will include logging statements to offer some insight into the steps executed during that module's operation. Including log statements in your code will cause those messages to also appear in the Console. Use Console to aid in developing your page or application.

Entry categories "info", "warn", and "error" are also referred to as the log level, and entries are filtered against the configured logLevel.