Article printed from World Book INFORMATION FINDER. WORLD, HISTORY OF THE (Introduction) WORLD, HISTORY OF THE. People have probably lived on the earth about 2 million years. But the story of world history begins only about 5,500 years ago with the invention of writing. The period before people began to write is usually called prehistory. Archaeologists have pieced together the story of prehistory by studying what the people left behind, including artwork, tools, ruins of buildings, fossils, and even their own skeletons. Such objects p ....