The multi jack cassettes or cassette modules have terminal blocks at rear suitable for different types of cables. They are mostly used in data centers.
Keystone jack is a female connector used in patch panels, keystone plates and keystone boxes. They are flexible and provide an easier installation, so to make a connection, the keystone jack must be pushed into a port and it positions itself easily.
Keystone adapters allow you to patch other types of cables into a patch panel.