Computer graphics programs offer you a variety of different tools and functions for your work as illustrators. One function that is provided by all graphics programs is the so-called Bézier curve.

The Bézier curve is an efficient tool for the creation of well-formed and complex curves in computer graphics. It is also a tool that demands a certain amount of familiarization due to its structure. As a result, there are users who genuinely appreciate this curve, as well as others who are desperate to learn more about its use.

What makes this curve so unique?
To answer this question, it is important to know the brief history of the Bézier curve. With the introduction of the first powerful computers at the end of the 1950s, it became possible to carry out automobile designs and calculations on these computers. Unfortunately, at that time there was no software capable of creating and representing the curves of an automobile effectively. Finally, the mathematicians P. Bézier of Renault and P. de Casteljau of Citroën developed the Bézier curve in order to solve this challenge. This development is also referred to as the break-through of "Computer Aided Geometric Design (CAGD)" and is seen as the basis for other curve models (such as NURBS = NonUniform Rational B-Spline).

How can we explain the Bézier curve to a user of a graphics program?
The Bézier curve basically consists of fulcrums (A) and tangents (B), as can be seen in the following graphic:

If you extend the tangents between two fulcrums theoretically, these build up a simply rounded edge that is represented by a curve.

If you wish to draw a simple curve as shown above, follow these instructions:
Click with the Bézier tool at point (A). Keep the mouse button pressed and pull out the tangent. Release the mouse button and click where the upper vertex (i.e. the next fulcrum) will be placed. Again, pull the tangent to the right side, while keeping the mouse button pressed. The left side of the tangent (B) will then be drawn automatically.

Release the mouse button and click where the last point (lower right side) will be placed. Keeping the mouse button pressed, drag to the lower right side. Finished!

With a little practice, you should be able to create the curve as depicted above. Afterwards, you should move the tangents (they are also called "handles") and the fulcrums with the arrow cursor. Then you can see, what single changes will affect.

In short, the concept of creating Bézier curves is as follows: 

• Place the first fulcrum and pull the first tangent in the drawing direction.
• Place another fulcrum located far enough away from the first tangent and pull the next
  tangent in drawing direction, and so on.