Activism is when people try to make the world a better place by speaking up and taking action about things that they care about. For example, if you really care about stopping climate change, you might join a group that plants trees or talks to government officials about passing laws to protect the environment. People who care about ending racism might join a protest or start a campaign to educate others about the harms of racism. Activism can take many different forms, but it's always about trying to make a difference and fighting for what you believe in.