hologram
A virtual three-dimensional image projection. Most commonly seen in sci-fi and space travel movies where a holographic projection is used for long-distance communication or a futuristic recorded message by projecting an image of the person talking. Also used in images to give a futuristic sense of technology: by having computer screens or digital tools projected into midair for people to use.
They differ from a normal object or person by either appearing to be made up of light, projection lines, possible flickering effects, and being somewhat transparent. Sometimes they might appear to softly glow.