World History has only recently emerged as a distinctive and vibrant field of study. Its origins arose from a cross-fertilization of economics, history, and comparative sociology, and from particular conjunctions of people and places in the 1980s and 1990s. World historians now, thanks to unprecedented access to quantitative historical data and international networks of scholars, can develop increasingly precise, formal, and detailed accounts of changes and comparisons across historical periods. However, our goal is not to create new master narratives or theories that predict a grand historical trajectory for mankind; rather we seek to better understand the similarities and differences among societies, and the likely consequences of those similarities and differences.