A public company is like a big club where lots of people can own a little piece of it. The club is called "public" because anyone can join, not just people who know each other. When you own a little piece, you get to vote on important things like who should be in charge of the club and how much money the club should spend.
To join the club, you need to buy "shares" which are little pieces of the company. You can buy them from the club itself when it first starts, or from other people who already own some. Just like a soccer club might sell tickets to a game, a public company sells shares to people who want to be a part of it.
But because there are so many people who own a piece of the club, it can be hard to decide what to do with all the money and who should run the show. That's why the club elects a group of people called the "board of directors". These people are in charge of making important decisions and listening to what the owners have to say.
When the club makes money, it can either share it with the owners (that's you!) through something called a "dividend" or it can use the money to make the club even better, like building new soccer fields or hiring better coaches.
And just like with any club, sometimes things don't go perfectly. If the club isn't doing well or if the people in charge are doing something wrong, the owners can speak up and try to change things.
In summary, a public company is like a big club where lots of people can own a little piece of the company and have a say in how it's run. They can make money from the company and have a say in how it's used. There are people in charge who make decisions, but the owners have the power to speak up if they don't like what's happening.