Radians
This is a very basic explanation of Radians, if you have never been taught Radians before.
Radians are another way of describing angles, as opposed to using degrees. Something similar to Radians is used in everyday life, when we use fractions. We say, "I want a third of a piece of cake," not, "I want 120 degrees worth of cake."
For a basic idea of Radians to how much "cake" or "circle" you have, divide the radians by "2 pi". To convert how much "cake" or "circle" you have to Radians, multiply the "cake" (or circle) by "2 pi"):
2pi => one whole circle pi => one half circle pi/2 => one fourth circle 2pi/5 => one-fifth circle pi/3 => one-sixth circle pi/4 => one-eighth circle
So, how much "cake" is pi/6? radians? => one-twelfth of a circle.