What does the Mercedes-Benz badge mean?

It stand for the three modes of transportion. By land, by air, and by sea. It's called 'the three-pointed star,' This came about when Gottlieb Daimer was staring into the sky one day and decided it should be a star Addendum:

It is a three pointed star, but was not arbitrarily decided. It symbolizes Daimler's pursuit of transportation over Land, Sea and Air. Three mediums, three points on the star.