Most of human history is not described by any written records. Writing did not exist anywhere in the world until about 5000 years ago, and only spread among a relatively small number of technologically advanced civilizations. These civilizations are, not coincidentally, the best-known; they have been open to the inquiry of historians for centuries, while archaeology has arisen only recently. Even within a civilization that is literate at some levels, many important human practices are not officially recorded. Any knowledge of the formative early years of human civilization - the development of agriculture, cult practices of folk religion, the rise of the first cities - must come from archaeology.
Even where written records do exist, they are invariably incomplete or biased to some extent. In many societies, literacy was restricted to the elite classes, such as the clergy or the bureaucracy of court or temple. The literacy even of an aristocracy has sometimes been restricted to deeds and contracts. The interests and world-view of elites are often quite different from the lives and interests of the masses. Any writings that were produced by people more representative of the general population were unlikely to find their way into libraries and be preserved there for posterity. Thus, written records tend to reflect the biases of the literate classes, and cannot be trusted as a sole source. The material record is nearer to a fair representation of society, though it is subject to its own inaccuracies, such as sampling bias and differential preservation.
In addition to their scientific importance, archaeological remains sometimes have political significance to descendants of the people who produced them, monetary value to collectors, or simply strong aesthetic appeal. Many people identify archaeology with the recovery of such aesthetic, religious, political or economic treasures rather than the reconstruction of past societies.
This view is often espoused in works of popular fiction, such as Raiders of the Lost Ark, The Mummy, and King Solomon's Mines where the field has become profitable fodder for entertainment. When such unrealistic subjects are treated more seriously, accusations of pseudo science are invariably leveled at their proponents (see Pseudo archaeology, below). However, these endeavors, real and fictional, are not representative of the modern state of archaeology.