So how many of you have ever heard of Alfred Wegener? No, he's not baseball player, rock musician or Hollywood celebrity. He is known as the father of continental drift. He was a meteorologist, studying climate in Greenland in the early 1900's. In those times, many scientists were true renaissance men, being knowledgeable in many subject areas. He began to make interesting observations, notably the presence of fossils in Greenland of plants resembling palm trees. How could palm trees have existed in such a cold climate? Well of course, basic astronomy told him that the poles of the Earth must always be cold due to the low angle of sunlight. The only logical explanation he could come up with was that perhaps Greenland had been closer to the equator. After examining a map of the world, he noticed that the outlines of the continents were such that they could be placed together. The most obvious fit was where the east coast of South America fits into the west coast of Africa. After much thought he theorized that the continents were once all connected in one large landmass, which he named Pangaea, which meant "all lands" in Latin. His theory was met by ridicule of course, because people simply thought the whole idea impossible because no known force could possibly move the continents.
The continents are not connected today, and if Wegener could prove that Pangaea once existed, then like it or not, with or without a mechanism for movement, then the continents must be moving.
Unfortunately Wegener died before his theory could be vindicated. Additional evidence such as similar rocks and minerals on the edges of continents, and remains of extinct fossils land animals led credence to his theory. Plate tectonics has replaced his original title of continental drift, as we now know that it is not the continents that are moving, but the lithosphere. The lithosphere is the crust of the Earth and the upper rigid mantle. It is broken into pieces which are moving and interacting, resulting in earthquakes and volcanoes.
Wegener is buried in Greenland, where his theory was born.