Okay kiddo, forging is kind of like playing with Play-Doh. You know how you can take a lump of Play-Doh and shape it with your hands? Well, forging is like that, but with metal instead of Play-Doh.
When people forge metal, they heat it up in a really hot furnace or oven until it gets really hot and soft. Then they use a special tool called a hammer to hit the metal over and over again, shaping it into the shape they want. This might be a sword, a tool, or even a piece of jewelry.
The really cool thing about forging is that the metal gets stronger as it gets hit by the hammer. It's like when you knead dough to make bread - the more you work it, the stronger it gets. So when you forge metal, it becomes not only the shape you want, but stronger too.
People have been forging metal for thousands of years. It's really hard work, but it's also really satisfying to take a lump of molten metal and transform it into something useful or beautiful.