I've experienced using quite a few different computers/operating systems, in my time, including...

• PC: Windows 3.x/95/98/ME/8/10 Professional

• Linux: Ubuntu/Raspberry Pi

I also remember owning home based computer game machines...

• Atari 520 ST FM: GEM/Graphics Environment Manager

• Commadore 64

• PSION XP II/Series 3a

My current operating system that I mostly tend to use at home is: Windows 10 Professional.