When looking at this post, the thing that popped out to my the most was that there were only 3 different shapes that could tessellate perfectly. In a way, this sort of bugged me because i thought, how could that be possible? Well on my search for tessellations, i came across multiple pictures that interested me and brought up a completely new thought.What if you used two different shapes? Yeah, its not your typical tessellation, but it gets the same job done. If you use octagons and you matched them up side by side, the space in between them would make a square. Example:

This got me thinking even more, how many different possible two-shaped tessellations are there? My opinion is that there are infinitely many. Which made me think even more.... A tessellation is almost just like a pattern that you see in elementary school. Like: Circle, triangle, square, circle, triangle, square... etc. So... a tessellation could be more that 2 shapes. how about 3? or 4? or 5? Here is an example of 3 shapes:

As you could see, this could become very complex. Having more than 5 shapes would become very difficult to follow.

http://www.mi.sanu.ac.rs/vismath/crowe/cr3.htm
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