-If the screensaver is active (the screen is blanked), this command will
-deactivate it just as if there had been keyboard or mouse activity.
-If locking is enabled, then the screensaver will prompt for a password
-as usual.
+This tells xscreensaver to pretend that there has just been user activity.
+This means that if the screensaver is active (the screen is blanked),
+then this command will cause the screen to un-blank as if there had been
+keyboard or mouse activity. If the screen is locked, then the password
+dialog will pop up first, as usual. If the screen is not blanked, then
+this simulated user activity will re-start the countdown (so, issuing
+the \fI\-deactivate\fP command periodically is \fIone\fP way to prevent
+the screen from blanking.)