Sometimes it comes installed with the computer, or it's part of some larger program package. This article is aimed at all who may have an interest in getting more out of whichever program they may have available. The program I am using here is Adobe Illustrator.
Every object has a mass and a contour.
Drag a rectangle around the image. To make fine adjustments, select the image and your arrow keys to move it in the desired direction. Illustrator has a preview mode and an outline mode. Preview is the normal view showing the images with colours and textures etc. Outline shows only the contours.