Weight.

A force is a push or pull.
One  reason the ancients thought the earth was flat was that they couldn't figure out what what would keep all us who lived "down under" from falling off. 

Newton (him again) suggested that all objects are attracted to each other, and that this force was proportional to the size of the object, and the distance apart they were. 

Fortunately, the size of this force between you and I is not enough is not enough to keep us stuck together. 
However, the Earth is so very massive, that it does exert a force on us that keeps us Earthbound. 

The gravitational attraction for objects on the Earth,  measured in Newtons is roughly 10 x your mass in kilograms. (9.8x to be exact) 
On the moon, it is  1.7 x your mass, and on Mars, it's 3.8 x your mass (not counting the weight of your spacesuit). 

Notice that your mass and your weight are different, even though we talk about them as if they are in everyday conversation. Your mass is simply how much matter there is in you. Your weight is the force you exert on whichever planet you happen to be on at the time. Click here for an on-line experiment. 
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