Petite, fat, skinny, or muscular. People come in all shapes and sizes but none of which can accurately be defined by the aforementioned terms. Instead, there are three body types that have scientific foundation - mesomorph, ectomorph, or endomorph.

These body types all have different characteristics, which means you are better off tailoring your workouts to whichever you belong.

Mesomorph (a.k.a., muscular): These individuals tend to increase their muscle size quickly and easily. They have athletic builds, lots of energy and tend to be aggressive when participating in athletics.
Potential negatives: poor flexibility, hips are generally same width as your shoulders, cardiovascular disease may become a threat if they become overweight.
Examples: Sylvester Stallone and Demi Moore

Ectomorph (a.k.a., slim): They usually possess a linear shape with a slight build. Ecto’s usually have less muscle mass than other body types. However, they may excel in cardiovascular activities.
Potential negatives: frail structure may cause these individuals to be injured easily. Dreams of becoming a professional football player may have to wait.

Examples: Tyra Banks and Tom Hanks

Endomorph (a.k.a., curvy): A soft flowing curvy body where body fat tends to settle within the lower regions of your body (i.e., hips, abdominals, and thighs). Most endomorphs have a blend of features from other body types.
Potential negatives: Due to their ability to put fat on pretty easily, they are inclined to become obese.

Example: Robin Williams and Marilyn Monroe