Forbidden Planet

Question: Can someone explain how all the special effects were done, such as the electronic blasters rays, and the sound effects? As the film was from 1956 there were no electronic keyboards then and the sounds are very futuristic.

Chosen answer: Many of the sound effects use an electictronic instrument called a theremin which was invented in 1919. You may hear it used more musically in The Beach Boys song "Good Vibrations." The visual effects would have been animated composites as used in Star Wars and Ghostbusters.