Microsoft and Apple operating systems have been around for about 30 years now, and for many of us, just the sight of the UI can provoke a strong sense of nostalgia. To do this, most people get their hands on the software and boot it up in some kind of virtual machine set-up, which can be quite a hassle for those that just want to take a quick peak.
There are a number of developers that have made this much easier, running these old operating systems (to some degree) right in the browser. Below we have a some links to where you can get a quick taste of Microsoft 1.0 all the way through to Apple's OS 8.6 and some of the more notable releases in between like Windows 95 running in right in the browser.
The Microsoft 1.0 operating system emulation, courtesy of jsmachines.net, brings up a basic version of the 1985 software (seen above). Although you can't save changes and it's in black and white, you can run some of the earliest Windows apps like Notepad and Paint. A site called VirtualDesktop.org has a number of Microsoft and Apple OS emulations available, one of which is Windows 95. This one isn't entirely functional so this is purely a nostalgia trip, but a quick look at Microsoft's first version of the Start menu will likely spark some old memories. You can also see Windows 3.1 in a much more useable state and Windows XP in action as well.
As for Apple's operating systems, developer James Friend has put together an emulation of Mac OS System 7 from 1991 complete with an image of the hardware itself (right). It is a little sticky and difficult to use, but there are a few games and apps to play with and it's interesting to see such an early version of Apple's OS that appears in many ways to look quite similar to today's (at least on the front end). VirtualDesktop also has a version of Mac OS 8.6 to check out. A significant release for Apple in that it was one of the latest versions put out before the company overhauled its system for OSX.
Unfortunately, we haven't spotted any older Linux emulations as of yet, but with the above links most of us should be able to find some of the very first operating systems we ever used. Which hopefully brings back positive memories and not ones of frustrating error messages.