Stereograms (or "auto-stereograms") are a special kind of images made to create an illusion of 3D vision. You don't need special equipment, nor 3D glasses, to see them; just a little practice.
If you have questions or need instructions, go to the FAQ.
These stereograms where made by me, with a program I developed during my scientific years, at the University of Buenos Aires (Argentina). They are optimized to be seen in a PC monitor, not to be printed on paper.