The legs and
upper body of an astronaut
floating in space form a natural angle of about 128.
People recovering from knee
surgery track their progress by achieving flexibility
to a certain angle measure.
To measure angles between joints, orthopedic
surgeons and physical
therapists, use an instrument called a goniometer.
is related to the number system of the ancient Babylonians.
Angles can be measured in radians
and grads as well