Our Earth is a huge ball of rocks and metals, formed about 4,500 million years ago. For millions of years, it was so hot that the rocks and metals were liquid. Then, very slowly, the surface cooled down.
Our planet has not always looked the way it does today. Hundreds of millions of years ago, the world was just one continent, surrounded by sea.
One Continent: Pangea
bout 200 million years ago, all the land was joined up into one huge continent, called Pangaea (Pan-jee-a). So dinosaurs could roam right round the Earth without crossing water.
Shifting Tectonic Plates
Slowly, over millions of years, the shifting plates began to pull this continent apart into two great land masses called Laurasia (Law-race-ia) and Gondwanaland (Gon-dwan-a-land).
The Late Triassic Period 225 Million Years Ago
Dinosaurs first appeared with the world was a supercontinent called Pangea. Gradually it split into two big land masses called Laurasia and Gondwanaland.
The Late Jurassic Period 145 Million Years Ago
By this time the land masses had drifted further apart. The northern land masses included Asia and Europe which was joined to North America. This land mass was drifting northwards. What are now separate continents of Africa and South America were joined together in one land mass that was drifting south.
The Late Cretaceous Period 66 Million Years Ago
Gaps between the continents had become far wider. The sea filled them and formed vast oceans, including the Atlantic.
Twentieth Century Earth
This is the world as we know it today, with wide stretches of ocean between the continents.
The map of the world will look very different millions of years in the future as the continents continue to move. North America and Russia are drifting towards each other and could even bump in about 50 million years time. The Atlantic Ocean is also growing wider by about 4cm a year.