Definition: Body fat is a lipid (fat) produced in the body, and this may be influenced by diet, exercise and genetics. Body fat percentage is that percentage of body mass that is not made up of bone, muscle, connective tissue and fluids; that is, everything else. (This is referred to as 'fat-free mass'.)
Examples:
In bodybuilding and weight training, muscle definition is enhanced when body fat percentage is low -- below about 6% in men and below 12% in women.
