The Royal 5 is an old model of flatbed typewriter. It was made by the Royal Typewriter Company, which introduced it in 1911.
The Royal 5 figures into the plot of Heavy Rain when Lauren Winter brings a copy of the Church Letter to Scott Shelby. Suspecting that the letter and the address on the envelope were typed with a Royal 5 typewriter, they meet with Scott's old friend Manfred, who bought the entire stock of Royal 5 parts back in 1964. Manfred confirms that a Royal 5 was used to type the address and says that anyone who owns a working one would have brought it to him for repairs. He goes to his office to look for his client list, which Scott says would help Lauren and him with their investigation, but is murdered by the Origami Killer before he can find it.