What is the Coding language?

Hello
It's standard javascript so you can interact and communicate with you website ( if you embed dynamo inside a webpage )
And it uses Box2D library.

Here's the flash version, it's the same thing, more or less :
http://www.box2dflash.org/docs/2.0.2/manual

You can also edit some levels to see how code is made, for example, this one:
https://dynamo.tools/editor#levels=570d126b47e08b014d000610 ( log in before clicking )

Select the green circle, then click on the edit code inside the body section. you will see the following line :

location.href=body.vars.link.value;

It means that when you click on this body ( the green circle ), the browser will load the link page passed inside the parameter in the vars section of the body.

Dont forget that you can have multiple projects and tabs loaded in the editor, and copy paste elements or group of elements from one to another.