In America, a Penny is a One Cent Piece
You may have heard the proverb, "See a penny, pick it up, and all day long you'll have good luck," if you're elderly and still recall pennies. The world of coins and paper money is gradually disappearing in favor of electronic trade, but the penny had a successful career. In the year 790 AD, the first penny was made available. That history is impressive.
Perhaps the most intriguing aspect of the penny in modern times, and especially in America, is that it doesn't exist. The coin is officially known as the American one cent piece, and "penny" is more of a colloquial term given that it has been used for well over a thousand years. If you name it a cent yourself, don't feel strange about it. Almost everybody does, even the US Mint. Naturally, they adhere to their own correct terms throughout the rest of their website.