ELI5: Explain Like I'm 5

Anti-particle

Have you ever heard of a mirror? When you look at yourself in the mirror, the person you see is your reflection, right? Well, particles also have reflections, but instead of being in a mirror, they are the opposite of the normal particle. So, if a particle has a positive charge, its reflection – or “anti-particle” – has a negative charge.

Anti-particles are really important because when they come into contact with their corresponding particles, they can annihilate each other and turn into pure energy. This is kind of like what happens when you mix two colors of paint together – they combine to make a new color.

Scientists use anti-particles to study the laws of physics and understand how the universe works. They even use them in medical technology like PET scans! But don't worry, even though anti-particles sound a little scary, they're not going to hurt you. They're just an important part of the wacky and wonderful world of particles and energy.