Yes, a moving square, from a couple lines of code, that can be easily changed to a twirly throbbing square, and can be shown on anyone's computer or mobile phone in the world by sharing a URL.

To get a moving square on the desktop twenty years ago took more lines of code, arguably harder to change to a twirly throbbing square, and usually copied to disk (or emailed) to show someone else by sharing the executable that may or may not run.

A moving square, from a couple lines of code, distributed to millions of computers, smart phones, other devices running various operating systems and zillions of different hardware configurations.

The last part is stunning and does not exist outside of browsers.

Proof of concept. You have to start somewhere.

Have you looked at any of the other Raphael demos?