713 music hall: 200 seating: GA8 meaning??

Okay what exactly does GA8 mean?? I know it’s a standing room at the 2nd floor but what exactly does GA8 means? My friend got GA7.

Sorry if this is a stupid question but I’ve never been to 713 before. Also, is the view actually great? Is it as exciting as the first floor pit? (Sad that I couldn’t get first floor tickets🤣🤣)