Imagine you have a toy that you like to play with, but you want to change some things about it to make it better. You could ask the people who made the toy to make those changes, but they might not want to because they have their own plans for the toy. However, if the toy is made in a way that allows you to see how it works and make changes yourself, you can make the toy better without asking anyone for permission. Free and open-source software is kind of like that toy.
Software are the programs that run on your computer or phone, like games, office apps, or photo editors. Some software is made by a company who wants to sell it to you, while other software is made by people who just want to share it with others for free. Free software means you can use it without paying any money, and open-source software means you can see how it was made and even change it yourself if you want.
Most toys and software are made in a way that the makers don't want other people to change them. But free and open-source software is made in a way that anyone can see how it works and change it if they want. This means that people all over the world can work together to make the software better, fixing mistakes or adding new features, without having to ask anyone's permission.
So, next time you want to play with a toy, think about how fun it would be if you could change it to make it even better. Or, if you're interested in software, think about how free and open-source software lets anyone be creative and make something new.