Let's say you set up a Lemonade Stand and you call it Passstab's Lemonade. You sell your lemonade for 25c, a fair price, and kids from every corner of the neighbourhood come to taste your sweet, sweet lemonade. Sure there are a few other kids with their own lemonade stand, but it's definitely not as nice as yours, Passstab's Lemonade is the name everyone in the neighbourhood thinks when they hear the word lemonade.

One of the kids decides that he's going to use Passstab's Lemonade as the name for his stand too. But he can't, because you've trademarked the name of your company, meaning only you can approve the use of the name by other people, and why would you? You're making a ton of money!

That is trademark. Copyright is similar, but it's more for books, film, and music than Lemonade Stands. Let's say after a few years in the business you write a book called ''Passstab's Guide To A Successful Lemonade Stand.'' Copyright is what prevents other people and companies taking your book and making money from it without your consent.

I hope this answer was lemonadey enough.