If you used a Mac in the 80s or 90s, you probably remember what is now called “Classic Mac OS,” the precursor to the OS known as macOS today. You’d think you’d have to find an old Mac on Craigslist to run that operating system again, but that’s not true: you can now try them all out in your browser.
Run Every Classic Mac OS Version in Your Browser! – Infinite Mac Updates
A site called InfiniteMac, created by Mihai Parparita, offers virtual machines running every major classic Mac operating system, from 1985 through 2001. Browse the collection, find something you want to try out, and click Run.
Everything loads directly into your browser, meaning you don't have to install anything. There are some stickies in each machine to help you find your way around, and a mounted hard drive full of games and goodies.
There’s even a special hard drive, called Saved HD, where you can store all the files you create. They’re stored locally on your computer, but any other operating system you open on InfiniteMac can access them. You can also drag files from your computer into the window and find them in a folder called “Outside World.” It all looks very streamlined.