Neutralization is like having two friends, one who really likes playing with toys that are purple, and another who really likes playing with toys that are green. They argue a lot about which toy is the best and they never really get along when they have to play together.
But then, you come along and ask them to play with a toy that is both purple and green. They are both happy because they get to play with something they like and they stop arguing. This is kind of what happens in neutralization chemistry.
In chemistry, there are two things, acids and bases that are kind of like the two friends who like different colored toys. Acids are things that have lots of hydrogen ions (H+) in them and bases are things that have lots of hydroxide ions (OH-) in them.
When you mix an acid and a base together, they stop being an acid or a base and become something else called a salt and water. The H+ ions from the acid combine with the OH- ions from the base to create H2O (water) while the salt is formed by the remaining ions that are left over.
This is important because sometimes the things we mix together in chemistry can be dangerous or harmful when they are in their original state. But by neutralizing them, we can turn them into something safe and useful, just like how the two friends in our first story stopped arguing and started playing nicely together.
So basically, neutralization is when you mix an acid and a base together and they stop being an acid or a base and become something else that is safe and useful.