Illustrator is a vector-based program. What this means is that it operates on math-plainly speaking- and imagery is created with said math. Photoshop does not operate this way. Therefore, many find Adobe Illustrator a little more challenging. Not because you have to figure out the math, but because you have to tell the computer what you want to happen in a more deliberate way. So, why vector? Well, vector images look great at any size. They look graphically clean and file sizes can be smaller. Illustrator is just a different beast compared to Photoshop and produces different results.
The pen tool in Adobe Illustrator is one of the most important tools to learn. It is a quite complex tool capable of producing a wide variety of marks. The pen tool in Illustrator requires some practice. The way it works is by creating Bezier curves through the placement of anchor points. By manipulating the handles associated with the anchor points, lines and shapes can be created.
The following video art lesson illustrates how to use the pen tool in Illustrator to create a vector illustration. This video covers only the basics. It is meant to be an introduction to the pen tool in Illustrator. With practice however, you can master the pen tool to make stunning artwork with Illustrator.