# 1.6.2. Quadratic and Cubic Bézier Curves

#### Quadratic Bézier Curve

A quadratic Bézier curve is a Bézier curve
of degree 2 and is defined through 3 points (P_{0}, P_{1} and P_{2})

#### Cubic Bézier Curve

A cubic Bézier curve is a Bézier curve of
degree 3 and is defined by 4 points (P_{0}, P_{1}, P_{2} and P_{3}). The curve starts at P_{0}
and stops at P_{3}. The line P_{0}P_{1}
is the tangent of the curve in point P_{0}. And so it is the line P_{2}P_{3} in point
P_{3}. In general, the curve will not
pass through P_{1} or P_{2}; the only function of these points is
providing directional information. The distance between P_{0} and P_{1} determines “how long” the curve moves into direction P_{1} before turning towards P_{3}.

Now by considering the applied knowledge about Bézier curves, experience the Cubic Bézier Curve in the following interaction part a second time by moving the blue circles.