Okay kiddo, have you ever seen on TV or in a movie when someone says "if you see something, say something"? Well, that's kind of like what Crimestoppers is.
Crimestoppers is a group of people who want to help stop crimes from happening. They work with the police to encourage people to tell them if they see or hear about a crime. But sometimes people are scared that if they tell the police, the bad guys might hurt them or their family. So, Crimestoppers lets people give tips anonymously, which means they don't have to tell their name or other personal information.
When someone gives a tip to Crimestoppers, they pass it on to the police so that they can investigate and try to stop the bad guys from doing more bad things. And if the tip leads to an arrest, the person who gave the tip could get a reward!
So, basically, Crimestoppers is a way for people to help the police stop crime without being scared or having to give their name. It's like being a superhero and helping make the world a safer place!