[opensuse] Package manager for command line?

Hello, What is the "official" command line tool to install packages on suse? I know there are apt, smart, zypper and maybe even more. But I'd like to know which one is the "official" tool that is installed by default on every suse system. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org