The Red Hat Package Manager, or RPM, is a low-level package manager developed by Red Hat for its Red Hat Enterprise Linux distribution. RPM is primarily used on distributions belonging to the Red Hat family (notable examples being Fedora, RHEL and CentOS) and distributions belonging to the SUSE family (notable examples being OpenSUSE and SUSE Enterprise Linux).
RPM is rarely directly used. Instead, it is generally used with a high-level package manager which provides things like dependency management and automatic fetching of binary packages from the internet.
yum is one such high-level package manager - it is typically used with Red Hat-family distributions.
zypper is another RPM-based high-level package manager - it is usually used under the distribution family it was developed for: SUSE.