Yack : An audio message
YackPack : The group with whom you Yack
Yacker : The voice behind the Yack
YackTrack : A series of yacks that play in sequence

PackHost : The Yacker hosting a pack
YackCast : The yacks you send out for all the world to hear
YackStack : A stack of messages
YackFAQ : Come on, you know what this is

YackCircle : A visual element, the circle you see on the screen