[link|http://www.ittopics.com/default.aspx?page=ed51cde3-d979-4daf-afae-fa6192562ea9&article=cd6af968-f287-4033-ba92-1f5bd09ab5e5|Oracle Dynamic Performance Views: V$ Views, V_$ Views and GV$ Views]
The actual dynamic performance views are identified by the prefix V_$. Public synonyms for these views have the prefix V$. Database administrators and other users should access only the V$ objects, not the V_$ objects.