Every website used to be like “www.example.com”. Now I rarely encounter this “www.”. Why did it even exist and where has it gone? I also used to run into websites with legitimate domains, but “ww1.” instead of “www.”, these were probably phishing sites, but how did this actually work on top of legitimate domains?
In addition to all the good answers, there also the case that most browsers just hide it nowadays. Go to google.com, you’ll see only that text in the URL field, the http(s)://www part is only shown when you click into the field, because as many have already said, it’s redundant in today’s infrastructure