The RED circle
Ok the Red Circle is your GEAR SCORE. You need to know this number for raids. We understand there are in-game gear score addons that number is NOT the same as this one and can not help Raid Leaders when forming a raid.
The BLUE circle
Ok the Blue circle is derived from your gear. The way this bar works is the Yellow are the raids that you should be doing for upgrades on gear. Green are the raids that you won't have any trouble doing but still may find upgrades. The Red bar are the raids that you aren't geared for yet.