Answer:
Continental drift or tectonic plates is a theory that explains the formation of the current surface structure of the Earth.
Continental drift is also understandable if you take pictures of each continents map and try to join them with another, for example, try to fit the map of western south India with Oman's southern region you will see they exactly fit each other, Science explains this as that the land had split and drifted to form what we see now, and this is known as continental drift or tectonic plates. This form was brought up by Alfred Wegener in 1912.
This theory is also the reasoning for the rising of mountains like the Himalayan mountains, which are having a rise in their height over time, the Himalayan mountains are believed to be belonging to a boundary of two plates that move towards each other and this is believed as the rise of India.