ok but that's not what you wrote. I quoted verbatim what you wrote and it's not correct, Docker images do not "contain full-blown operating systems as they are

ok but that's not what you wrote. I quoted verbatim what you wrote and it's not correct, Docker images do not "contain full-blown operating systems as they are meant to run arbitrary applications" unless you decide to put a full-blown operating systems in them but that's your choice, you definitely don't have to and everyone recommends not to