Is Split Testing a Good Control?

So split testing is, or no, they're known as AB testing, AB testing. Button color is the most simple to someone who's just starting an e-commerce. My developers have shown me that there's nothing that can't be split tested on a website. So does that kind of specialisation help? That's quite helpful. The other question I had, so there's everybody throws around a term, statistical significance. What are you looking for there? And then also, do you think it's good ever to test a lot of variables? Or should you always be doing like one or two kind of max? Totally. If something is stat SIG or not, every single piece of