Ultraviolet (UV) light is electromagnetic radiation with a wavelength shorter than that of visible light but longer than X-rays (from 400 nm to 10 nm in wavelength). These geeky tattoos can only be seen under a black light lamp, which emits long-wave UVA radiation and little visible light. Fluorescent black light lamps use a phosphor on the inner tube surface, which emits UVA light instead of visible light. Click here to view the first image in today’s viral picture gallery. Continue reading for a viral video of the five funniest parking lot FAILS.