Mirrors reverse left and right. Your reflection shows your left as right and vice versa.
Mirrors actually reverse front-to-back (depth), not left-to-right. We perceive it as a left-right reversal because we map our own body onto our reflection. If you raise your right hand, your reflection's right hand also goes up. The confusion arises from how we mentally orient and interpret mirror images.
Reception
Sources
- Physics Classroom: Mirror Images REFERENCE
- Stanford Encyclopedia: Mirrors and Reflection REFERENCE