by Richard Stallman
Could there be a rocket that is totally free software? Should we demand that SpaceX liberate the software in its satellite launching rockets? I don’t think the person who asked me this was serious, but answering that question may illuminate similar issues about the sorts of products people really buy today.
As far as I know, software as such is not capable of generating thrust. A rocket is necessarily principally a physical device. But it may include computerized control and telemetry systems, and thus software.
If someone offered to sell me a rocket, I would treat it like any other appliance. Consider, for instance, a thermostat. If it contains software to be modified, all the software in it needs to be free. If, however, the software in it need not ever be altered, and it communicates only through some limited interface, such as buttons on the control panel, a TV remote control, or a USB interface with a fixed set of commands, I would not consider it crucial to know what is inside the thermostat: whether it contains a special-purpose chip, or a processor running code, makes no direct difference to me as user. If it does contain code, it might as well have a special chip instead, so I don’t need to care which it is.
I would object if that thermostat sent someone data about my activities, regardless of how that was
— source gnu.org