History is the study of past events, including the discovery, collection, organization, presentation and interpretation of these events. Historians use a variety of sources to help construct history, such as written documents, oral accounts, art and material artifacts. Historians seek knowledge about the past, aiming for accuracy and objectivity. The discipline of history has evolved over the centuries, and it continues to evolve today. The study of prehistoric events is sometimes called prehistory, while the period of history beginning with the invention of writing systems is known as ancient history. The discipline of history has been criticized by those who argue that it is biased, incomplete and full of holes, but historians also have been accused of being too subjective and prone to inventing their own histories.
Despite the many arguments about the nature and value of history, most modern nations encourage its teaching in some form. One of the most important reasons for this is that history helps provide a sense of identity. For example, studying the history of a family can provide information about genealogy and (at a more complex level) evidence about how a family has interacted with larger historical change. The same is true of a country, an institution, or even a social unit such as an ethnic group in the United States.
Professional historians are keenly aware that the idea of an objective history is an illusion. A single event can take on thousands of different meanings when interpreted by all sorts of people who import their own prejudices, assumptions and philosophies into the formulation of history. The most egregious example of this is the argument over whether or not there was actually a Trojan War as the great Greek poet Homer describes it.
The truth is that a simple list of dates, supplemented by information about population growth rates, economic resources and church attendance, is insufficient to comprehend the history of 20th-century world experience. This is because a century of experience is an organism, ever growing, and the emergence of new phenomena requires us to rethink our ideas about earlier ones.
It follows that a historical account is constantly evolving and must be kept up to date, although it is a difficult and time-consuming task. It is also a risky endeavor, for it can easily be used as a weapon in culture wars by those who wish to legitimize or discredit actions and events that occur in the present. It is not, however, a discipline that should be stifled.
The real challenge of history lies not in learning the facts about a particular period but in discovering what those facts mean. This involves learning to distinguish between the objective, factual nature of a source and the subjective conception that it has been given by its author or the reader. This is a task that requires the attention of all of us, whether or not we regard ourselves as historians.