Magnitude is used in astronomy to indicate how bright a star is. Because of historical reasons the lower the magnitude the brighter the star. Now, if you measure the brightness of a star in the sky...
Apparent Magnitude is the star's brightness as it appears from earth, while, Absolute Magnitude is the apparent brightness of a star if viewed from a distance of 32.6 light years away.
Apparent magnitude is the brightness of an object as seen from Earth without any atmosphere.
Absolute magnitude is the brightness of an object as seen from a predetermined distance, depending on...
Apparent magnitude is the measure of how bright a star appears to be from our vantage point. Absolute magnitude is the measure of how bright a star would be if it were located 10 parsecs from earth.