which Operating System have you used?

[SKYNET]

there are more different OS that you can choose in the polls.

[Damião de Góis]

I have used... DOS, Linux (Red Hat, Fedora, Ubuntu), and several versions of Windows.

[arcticwolf]

All of those you specified and many others, can't even remember them all, most of them are history now. Though the coolest graphical interface was the BE OS. Too bad it is all but forgotten now.

[safinator]

Windows 7

[Leadchucker]

DOS,Windows 95,98,2000,ME, XP and 7

[The Lawspeaker]

Linux and Windows 7. I have returned to Windows 7 and dumped Linux. But before that I have used Vista, XP, 2000, 98 and the whole list down since my childhood. Before that DOS. And still I don't understand computers

[Vasconcelos]

I've only used windows OS', currently using 7.

[Holle Bolle Gijss]

I started of using DOS, then on to Windows 2.0, Windows 3.0/1, switched to OS/2 Warp for a while and through the years used all Windows versions uptill Windows 8 Consumer Preview wich obviously is my current OS.

[Matilda]

Windows XP, Vista, 98, 7
Linux

[Supreme American]

It's not letting me choose one and the selection only goes as far back as XP so I can't answer it.