The Fabrini were a species of humanoids from the Fabrina system. Ages ago, they determined that their home sun would enter a nova phase. To ensure their survival, they constructed the worldship Yonada and sent survivors on a predetermined course for a colony planet. This ship was controlled by a powerful computer, but over the years this computer came to be perceived by the Fabrini as a god, referred to as the Oracle of the People, as they lost all of their old knowledge of their origins.
In 2269, the USS Enterprise intercepted Yonada and found it on a collision course with the populated planet Daran V. The crew of the Enterprise was able to correct the navigational error and get the worldship back on its original course, simultaneously deactivating the Oracle and allowing the Fabrini to make their own way.
The Fabrini had sophisticated medical knowledge. For example, they possessed the cure for xenopolycythemia, a disease for which, in the mid-23rd century, the Federation had no cure. (TOS: "For the World is Hollow and I Have Touched the Sky")