In the movie "Ghost," the term "ghost" refers to the spirit of Sam Wheat, who is murdered and becomes a spectral presence. His ghost is unable to move on to the afterlife until he resolves unfinished business, particularly protecting his girlfriend, Molly, from danger and helping her understand the truth about his death. The film explores themes of love, loss, and the connection between the living and the dead, emphasizing how love transcends even death.

In the movie "Ghost," three types of ghosts can be identified: 1. **Spirits of the Departed**: These are souls who have unfinished business or unresolved issues in the living world, like Sam, who seeks to protect his loved ones. 2. **Vengeful Spirits**: These ghosts are driven by anger or a desire for revenge, often manifesting through negative energy or actions against the living. 3. **Guiding Spirits**: Some ghosts serve as guides to the living, helping them navigate challenges or provide comfort, exemplified by the character of Oda Mae Brown, who aids Sam in his quest.

In the movie "Ghost," Swiss, played by actor John Turturro, leaves the ghost of Sam Wheat (Patrick Swayze) and his girlfriend Molly Jensen (Demi Moore) because he realizes that helping them is putting him in danger. He is a medium who initially assists Sam in communicating with Molly, but as the plot unfolds, Swiss becomes increasingly aware of the risks involved, especially with the antagonist who is responsible for Sam's death. Ultimately, he decides to distance himself to protect his own safety.

As of my last update in October 2023, "Ghosts," the popular TV series that originated from the UK and has a U.S. adaptation, has been renewed for a fourth season. The U.S. version continues to gain popularity and has received positive reviews, leading to its renewal. For the latest information on release dates and episodes, it’s best to check the network's announcements or official social media channels.