new to fored induction

i recently bought a vortech 6psi setup and my girlfriend wnet on and bought me autometer boost and vacuum gauges.....honestly i dont know hot to reed the vacuum one...can someone help?

what are the #'s on the boost gauge?? does it go 30-0-30 or 0-30. If it goes 30-0-30, the left side is in. of vacuum, and the right side is boost psi. The 0-30 reads boost only.

30 can also be substituted for 15.

Chris

2 seperate gauges...boost is 0-30 psi and im not sure of the vacuum #'s..but i dont know how to read vacuum pressure....whats it mean