I take it you aren't a programmer.
1) most everyone learns to code with a short demo.
2) short demos for learning to program and understanding concepts are essentially spaghetti free -- the problem is you can't even do the simplest "hello world" in walled app gardens that require elaborate toolkits and permissions.
3) source from the fine article: originally published in Proceedings of the ACM National Conference, Boston (August 1972)