Coke is like a really strong and tough cookie made from coal. But instead of being soft and yummy like a regular cookie, coke is baked in a special oven to make it super hard and dry. It is used as a type of fuel that is often used to make electricity in power plants or to heat up things in factories. Think of it like putting a really strong and long-lasting log in a fire to keep it burning for a really long time. Coke is made from coal because coal has a lot of energy stored inside it, and coke is a way to release and use that energy.