Evil typically means something which is morally bad or wrong. People may say that an action which hurts people is evil.
Some people say that an action that breaks certain rules, like the Ten Commandments, is evil. Others say anything that God forbids is evil. A person or a group that does evil things may also be called evil.
People disagree on why people do evil things. People disagree about why evil exists. There are many debates and disagreements about the nature of evil.
Some cultures use demons to represent evil. This photograph shows a sculpture of a demon from Afghanistan.
Text adapted from Simple English Wikipedia, Creative Commons Attribution-ShareAlike License 4.0.
Head of Demon, Afghanistan, 3rd or 4th century, Musee Guimet. Photo by Vassil on Wikimedia Commons. Public domain