Absolute Magnitude:

Absolute magnitude is the true brightness of a star. The true brightness of a star would show if the star was seen from a distance
of 32.6 light-years from earth. If our sun were 32.6 light-years away, it would be a fifth magnitude star (+5). -5 through +15 is the average range for most stars. Every star has absolute and apparent magnitude, however, the relationship between the two depends on the distance between Earth and the star. Stars that are less then 32.6 light-years away appear brighter then they would if they were 32.6 light-years away. These stars have apparent magnitude that is lower then their absolute magnitude.
The lower the number, the brighter the star. Picture provided by myself using paint.