Open-source hardware is hardware whose design is made public so that anyone can use, modify, and build upon it. This can include things like computers, phones, cars, and robots. For example, If a company creates a computer and makes the design open-source, anyone can take the design and build their own computer from it. They can also customize the design and make it better by adding new parts or making changes. This makes it easier for people to make new, unique creations that can help solve problems for everyone.