How does one-way glass work and what makes it possible for people to see through it from one side but not the other?

One-way glass, also known as a two-way mirror, works by having one side brightly lit and the other side dark. This creates a difference in light levels that allows people on the dark side to see through the glass to the bright side, while those on the bright side only see their own reflection. This effect is possible due to the way light is reflected and transmitted through the glass, creating a one-way viewing experience.