The Olmec Civilisation is one of the most important civilisations ever. This is because it is a cultural hearth. Unless new evidence shows that the people of the Desert Southwest of North America or the Eastern Woodlands (with sites like Watson Brake or Poverty Point) were the actual inspiration for Olmec civilisation, then it was the Olmec who laid the foundation what would become a long line of New World civilisations including the Mixtecs, Toltecs, Aztecs and most importantly of all, the Maya.
Why are the Olmec given this distinction? Well, for one, monumental architecture such as the massive Olmec Heads show a need for organized labour. Second, large settlements like La Venta, San Lorenzo and Tres Zapotos, listed in order from earliest to latest, attest to city living rather than hunting and gathering. Third, the Olmec invented a writing writing system, a hallmark of a culture bursting into civilisation. If one book is correct which stated India, Persia, China and Egypt's writing systems were built upon Sumerian Cuneiform, than the only true written language ever invented independently were Sumerian Cuneiform and Olmec Hieroglyphics. All other writing systems can be traced to these two. Fourth, the Olmec practiced large scale agriculture. They grew the all important 'three sisters'; maize, squash and beans and a fourth of almost equal importance, the chili pepper. Avocados were another major food crop and cotton was important for the manufacture of clothing. Fifth, the Olmec, like the Babylonians, made huge achievements in math and astronomy. The Olmec discovered zero, created a calender and watched the stars. Finally, the Olmec had extensive trade networks. Obtaining luxury goods via trade requires specialisation and a noble class wealthy enough to buy non-essential items like gold or jade. The Olmec made items of florid materials such as obsidian and turqoise. Jade was also used by the Olmec. The only source of Jade in the region is from the Motagua River valley in eastern Guatemala.
With the growing interest in Mesoamerican Archaeology, the Mayans and Aztecs often get all the credit. However, groups like the Toltecs, Mixtecs and most importantly, the Olmec deserve far more research, discussion and interest.