https://www.wired.com/story/physicists-take-their-closest-look-yet-at-an-antimatter-atom/

The laws of physics, as experts currently understand them, dictate the following: Every fundamental particle has an antimatter twin. The electron, quark, and muon, for example, are paired with the positron, antiquark, and antimuon, respectively. Each antiparticle weighs exactly the same as its twin, but exhibits precisely the opposite electric charge. If the twins meet each other, they annihilate, often to produce light.

Since physicists discovered the first antimatter particle in 1932, the substance has become, in some ways, quite mundane. Researchers have found that lightning in thunderstorms generates positrons; when they meet nearby electrons, the two annihilate each other. Bananas, which contain trace amounts of radioactive potassium, emit a positron every 75 minutes. When they come into contact with electrons, the two also promptly annihilate, with no noticeable effect.