The Great Ones are the so-called "gods" of the Dreamlands, but they are not related to the Old Ones as they are not as powerful as the Great Old Ones and are not even as intelligent as most humans. In fact, they are more akin to mortal humans who can be wounded and deceived.
They are known to listen to the thoughts and prayers of humanity, but their purpose is unclear. However, they are protected by the Outer Gods, especially Nyarlathotep. However, Nyarlathotep treats them with contempt and thus it is unknown why he even bothers to protect them.