Okay, so imagine you're at a big party with lots of people. Some of the people have different skin colors than you - they might have brown skin or black skin or yellow skin. These people are called "visible minorities."
Now, the word "minority" means they are only a small group compared to everyone else at the party. So even though they look different, they might only make up a small part of the whole party.
Sometimes, people treat visible minorities differently because of their skin color. This is called "discrimination" and it's not nice. We should always treat everyone at the party with kindness and respect, no matter what they look like.