Alright, cauldron is a new, upcoming editor where it uses JavaScript and HTML instead of lua. It has similar hierarchy files to Roblox studio, and it has more colors. WebSim is a website where people can make their own fun, custom websites in that website. I’m pretty sure that people imported WebSim and/or other websites to castle by using cauldron.
Cauldron Beta is an editor like Castle's editor but you can't use blocks of code (rules), instead, it's replaced with JS and HTML coding. You need to fill out a form to get it.
WebSim on the other hand is a website that lets you make sites using Artificial Intelligence.