gnus-novice-usernil, you are either a newcomer to the World of
Usenet, or you are very cautious, which is a nice thing to be,
really. You will be given questions of the type “Are you
sure you want to do this?” before doing anything
dangerous. This is t by default.gnus-expert-usernil, you will seldom be asked any questions by
Gnus. It will simply assume you know what you're doing, no
matter how strange. For example, quitting Gnus, exiting a group
without an update, catching up with a group, deleting expired
articles, and replying by mail to a news message will not
require confirmation.gnus-interactive-catchupnil. It is t by
default.gnus-interactive-exitt by default.