Travelling back in time
Those of us who grew up with computers have witnessed great change: from the hulking tower PCs of yore to the pocket-sized smartphones of today and from blinking green screen cursors to 4K graphical displays.
For those old enough to remember wrestling with a command line or battling Windows' blue screen of death, it's never been easier to relive those early memories of computing.
These virtual trips down memory lane come courtesy of emulators that run directly in the web browser: offering the chance to experience everything from the birth of personal computing in the early 1980s to the golden age of Windows in the late 1990s.
Here are some of the classic operating systems you can run in your browser.