The COW programming language is a Turing Tarpit language that works like a turing machine. It is a variant of the popular esolang Brainf**k. If you're new to COW then follow along the comments in the code to understand some of the basics. Here are some resources if you want to learn more.
A Great video on COW.
An online javascript COW compiler.
Read about COW in the esolang wiki.
Here's a great proof of COW's turing completeness.