UNIX is basically a simple operating system, but you have to be a genius to understand the simplicity.
— Dennis Ritchie

To hackers, DNA is just another operating system waiting to be hacked.
Marc Goodman operating system quote

There is no neat distinction between operating system software and the software that runs on top of it.
— Jim Allchin

There's no other company that could make a MacBook Air and the reason is that not only do we control the hardware, but we control the operating system. And it is the intimate interaction between the operating system and the hardware that allows us to do that. There is no intimate interaction between Windows and a Dell notebook.
— Steve Jobs

Nokia and Research in Motion needed a modern operating system. They could have bought Palm or Android before Google did, but they didn't. Today, it's probably too late, and at the time they would have been criticized for overpaying, but as they say - shift happens.
— Marc Andreessen