<i>When you boot Linux, the init system loads the drivers you need, turns on your network connection, fires up the necessary system service and then loads the desktop. Without an init system, you have no way to do anything.</i><p>Actually I'm pretty sure it's udev that handles module loading these days (which isn't related to the functions of init(8) and process management, even if it's part of systemd now), or alternately one can use the kmod tools manually.<p>This is a misleading interpretation in general. The init system (though really the process manager) <i>starts the services</i> to enable all these things. The simplest form is just a synchronous tool that exec()s binaries.