Most fundamentally, doing world history involves the study of cross cultural events or phenomena. History may be defined as research into how cultures develop through time. World history is more general than traditional history and emphasizes trends that transcend cultural boundaries.
World history stresses the treatment of interaction between societies.
In eras where such interaction is limited, it compares different patterns of development around the world. Hence, a world history study may involve cultures that actually had contact and influence on one another, or cultures that went through various stages of development with little or no outside influence. Since history is full of this kind of material, the number of possible world history treatments is very large. World history tends to be more superficial and general than local or national histories. This is not meant in a negative way, but in the sense of a comprehensive view of history.