Imagine you and your friend want to start a lemonade stand, but you don't have enough money to buy all the supplies you need.
So you ask other people if they want to help you out by giving you some money, and in return, you give them a special piece of paper that says they own a tiny part of your lemonade stand. That special piece of paper is like a "stock."
Now, if your lemonade stand becomes really popular and makes a lot of money, then your friends who have the special pieces of paper (or "stocks") can make some money too.
They might get some of the profits, or they can sell their pieces of paper to someone else for more money than they paid for them.
But if your lemonade stand doesn't do well and nobody wants to buy your lemonade, then your friends might not be able to sell their special pieces of paper for as much money, or even at all.
Buying stocks can be a bit like taking a chance on your lemonade stand doing well or not.
It can be a fun way to invest in a company you believe in. One thing to keep in mind: there's always a risk involved when investing in stocks.
Usually we say: the higher the risk - the higher the chances of profits as well.
We need to find the opportunities that offer us the lowest possible risk while preserving the highest possible profits.
That's called a high risk / reward chance then.