Perhaps you watched the Billboard Music Awards and were aghast (or impressed) by Michael Jackson's performance from beyond the grave.
from beyond the grave. Or maybe you were at Coachella and caught a resurrected Tupac onstage with real-life Snoop Dogg. Hell, let's say you were wooed by India's Narendra Modi in his recent holographic stump speeches. Maybe none of the above? Well, either way, here's a bit of disappointing news: None of those were true holograms, despite our dreams of a sci-fi future. The aforementioned performances are a product of a centuries-old technique called "Pepper's Ghost." You might've seen this on a pretty grand scale during a family vacation to Disneyland, too. The park's Haunted Mansion ride uses it extensively, especially during the ballroom scene where "ghosts" are dancing all over the place. The key difference between what we're seeing now and what's been used for the past few hundred years? The tech being used has gotten much more advanced.
Gallery: Hologram performances | 13 Photos