Public history is, essentially, the field of making history accessible to the general public. Usually this takes place through creating and updating exhibits in museums, but also at historic sites (like Gettysburg), national sites (like the Washington Mall) or at memorials (like the Jefferson Memorial). The people who run these places are known as Public Historians, which typically require at least a minimum of a Master's degree for nearly all positions. I myself am studying Public History at my university as well, and it is done along side with studying my thesis topic which is within the realm of the American Revolution. If you have any further questions, please just let me know. Hope this helped.