ELI5: Explain Like I'm 5

On War

A war is when two or more groups or countries fight against each other. All sides try to get what they want by being stronger than the other group. Groups of people use lots of different kinds of weapons such as guns, bombs, and tanks to try to win. It's very dangerous and lots of people, including innocent people, get hurt and even die. Wars can also cause big changes in how people live, especially when lots of cities and buildings get destroyed.