Linux is not so much a platform as a toolkit for building them. Some Linux-based systems are very open. Some are completely locked down via code signing (e.g. many routers or DVRs).<p>Not that many Linux users compile binaries directly from source - and if they did it would completely bypass the protection of the official repositories. Fundamentally there&#x27;s an unavoidable contradiction here: if you only allow installing software from the official repositories then you have a very locked down system, and if you allow installing software from outside the official repositories then the system is unsafe. Windows went for the second option; contrast with iOS which goes for the first. There are Linux-based systems that take the one approach and Linux-based systems that take the other, but both have their downsides.