"Chemlambda is a graph rewriting system derived from graphic lambda calculus which can be seen as a simple model of chemical or biological computing."

here are demonstrations of the graph rewrite rules:

http://chorasimilarity.github.io/chemlambda-gui/dynamic/move...

the front page is a better start: http://chorasimilarity.github.io/chemlambda-gui/index.html

as is the FAQ: https://chorasimilarity.wordpress.com/2015/02/19/what-can-i-...

I am still having trouble to understand it. Is there something like an elementary picture/animation and it's mapping to lambda calculus (or a step)?

I agree. This looks amazing. Absolutely gorgeous. This really was done with just using JS? wow. But I have no idea what I just watched.

It's quite cute, but I'm surprised that you're surprised that JS can do it - it's only a few hundred moving objects, and JS has within-order-of-magnitude of native performance.

For shinier stuff, see the demoscene eg https://www.youtube.com/user/Annikras . Demoscene programmers love generative systems, especially when targetting the 4 kilobyte executable category. For example this one, which looks like a distorted Menger sponge: https://www.youtube.com/watch?v=E3qn1RsJlUM

Other things you ought to take a look at:

Sauerbraten in JS, called Bananabread¹, and jor1k an OpenRISC emulator running Linux². Although the latter uses a relay for networking.

1: https://developer.cdn.mozilla.net/media/uploads/demos/a/z/az...

2: https://s-macke.github.io/jor1k/demos/main.html