A right angle is a straight line and a rounded corner is a ray. Right? thank you

An angle is defined as a graph consisting of two rays with a common point. Since it is "two rays with a common point", the sentence "a right angle is a straight line" is wrong, because there is no point on the straight line.

A fillet is defined as the angle formed by the rotation of light around its endpoint when the starting edge and the ending edge are completely coincident. The fillet is actually a figure with two overlapping rays, so it is not easy to say that "the fillet is a ray".