Some of our computer club meetings have featured “simulated” computers (see Simple Computers and Simple Drawing Computers). But there are also on-line simulations of existing applications and entire operating systems. These are often written in JavaScript and run right inside your browser. Here are a few examples:

• Windows 98: https://98.js.org/ (source code)
• Windows 98: https://rahul.io/ (source code)
• Windows XP: https://winxp.vercel.app/ (source code)
• OS-JS: https://demo.os-js.org/ (source code)
• Windows “93”: https://www.windows93.net (not open source)

There are also individual applications available such as:

• Paint: https://jspaint.app (source code)