A harbor is like a parking spot for boats and ships. Just like how you park your car at a parking lot, boats and ships park at a harbor.
Harbors have a special area that is called a dock. A dock is like a long pier made of wood or concrete that goes into the water. Boats and ships can tie themselves up to the dock so they don't float away.
Harbors can be big or small. Some harbors are just a tiny spot where a few boats can park, while others can hold hundreds of boats at once.
In addition to being a parking spot for boats, a harbor can be a place where people can buy things they need for their boats. There might be shops that sell fishing gear or boat parts, or places to rent a boat.
Harbors can also be an important part of a town or city because they can bring in money from tourism. People might come to visit a harbor to go on a boat ride or see the boats that are parked there.
Overall, a harbor is a place where boats and ships can park and people can buy things for their boats.