Pangaea was a big super-continent of Earth. A super-continent means a very large area of land made up of several continents we know today. Pangea formed during the Mesozoic era three hundred million years ago. Nearly all the countries we have today were part of Pangaea. Many mountains today were made in this supercontinent. Pangaea was surrounded by one big ocean called Panthalassa.
Pangaea broke up during the Jurassic period 180 million years ago and it split into two continents: Gondwana in the South and Laurasia in the North. After this they split again into the continents we have today.
Scientists think that there were two super-continents before Pangea, one called Rodinia which was made 1,100 million years ago, then split 750 million years ago and one called Pannotia which was made 600 million years ago, then split 540 million years ago.
The Tethys Ocean has been around for millions of years; it probably was around when these super continents existed. During the Triassic period, the Tethys Ocean was located to the east of Pangaea and Laurasia. During the Jurassic, when the supercontinent split into Gondwanaland and Laurasia, the south-eastern opening to the Tethys Ocean became tighter, thus making the Tethys Ocean more contained. During the Cretaceous, Gondwanaland split into the continents of Africa, Australia and India. India was drifting through the Tethys Ocean; but now the Tethys Ocean is probably part of the Indian Ocean. Laurasia wasn't always part of the two Jurassic cotinents; it was also part of Pangaea. Laurasia was the northern part of Pangea. Laurasia stayed Laurasia for millions of years while Pangea split and shaped into a different continent called Gondwanaland.