# What is the real meaning of "degree mode" and "radian mode"?

In order to understand this, think about how we get the degrees. Take an angle with a fixed and a variable side. You can rotate the variable side until it completes a full circle. By convention, we decide that the full circle represents ${360}^{0}$. One degree is just that angle divided in 360 equal shares. The best analogy I can think of would be that between degrees and percentages. Both are just expressing proportions relative to a whole.