While I don’t personally consider them “Ghosts”, as a matter of covering all the bases I should spend a very few minutes on what are known as Living Spirits. 

These are rare and to the best of my knowledge there is nothing more than anecdotal evidence of their existence, which is due in part to the fact that they aren’t tied to a location, are usually one time occurrences, and are unpredictable in nature.

The usual story behind these manifestations goes in one of two directions.

The first is the person to whom a close friend or loved one appears even though they may be miles away. 

The loved one in question may be in danger and appearing to ask for prayers or help of some other kind. They may actually be on their deathbed and appearing to say goodbye. Some call this a “Moment of mortality ghost”.

The other occurrence is when the person observing the manifestation is the one in danger, with the apparition arriving to relay a warning or to help in some other way.

You could make the argument that this type of apparition is a familial as I described previously.

However I choose not to do so for the simple reason that the person in question is alive, at least at the moment of manifestation.