Continental drift

Once upon a time, a really, REALLY long time ago, the world was just one big supercontinent called Pangaea. But then things started to move around. Imagine if all the different pieces of a puzzle started to shift and slide around, that's kind of what happened to the Earth's land.

The Earth's crust, which is the hard outer layer of the Earth that we stand on, is broken up into different pieces called tectonic plates. These plates aren't just random pieces, they fit together like a jigsaw puzzle and they float on a layer of hot liquid rock deep below the crust called the mantle.

Now, sometimes these plates move apart, like when you pull a sandwich apart. When they do that, it creates a gap, which we call a rift valley. Other times these plates crash into each other and push up huge mountains, like the Himalayas.

So, as these plates move around, they pushed and shoved Pangaea until it eventually started to break apart. Over millions and millions of years, the different continents drifted apart to create the world that we know today.

So that's continental drift in a nutshell - the idea that the Earth's continents used to be stuck together and have drifted apart over a really long time.