how is there more gravity on earth than there is on the moon and why ??

Question: how is there more gravity on earth than there is on the moon and why ??

Asked by m3akinm3htxx to Sarah on 14 Jun 2010 in Categories: General.
- Sarah Burl answered on 14 Jun 2010:
  
  The moons gravity is 1/6th of the earths gravity because of its size. Gavity is based on rotation of the planet and density of the atmosphere. I was never really that great at physics so that is amount the extent of my knowledge on this, sorry!

Question: how is there more gravity on earth than there is on the moon and why ??