Caption: A cartoon illustrating chaos and chaotic evolution.

Features:

1. We will not fully describe chaos, but it is the property that causes a system to have super-sensitivity to initial conditions AND to evolve in a very complex way.

2. A chaotic system, even though completely obeying determinism in principle, evolves eventually in completely unpredictable way as a usual rule. The usual rule is because you can never exactly calculate continuous quantities, and so at some point calculation error will cause you to leave the path of true evolution. At that point, the super-sensivitivty and complex evolution conditions lead the true evolution far away from the calculated evolution.

3. In the cartoon, two systems start from nearly the same initial conditions. But since the systems are chaotic, their evolution eventually becomes completely different. Unless, the initial conditions were exactly the same, very different evolution must occur eventually.

4. Many systems actually exhibit chaos. But we don't see chaos much in the human world. We don't build our machines to be chaotic. No one wants a chaotic car engine.