Theory:

History is the study of Past.
 
Historians write history with the help of Sources. Studying history helps us to understand our past, which in turn helps us to understand our present. It helps us clarify what we are doing now and how things happened in the past.
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Studying history can also provide us with insight knowledge about the \(origin \)of a particular culture. Sometimes through reading history, we gain knowledge on cross cultures.
Historians do not reconstruct the past. They throw light on the hidden past which should be known to all to make the future better.
 Thus the best and most concise definition of history is:
The knowledge of the past produced by historians, together with everything that involves the production, communication, and teaching.
 
The sources used to write history by historians are categorized into Primary sources and Secondary Sources.
Primary Source plays a central role of evidence for writing History, as it is believed that primary sources are not biased. The primary source always gives accurate information. In concise terms, we can say that all archaeological sources are Primary Sources.
Example:
Monuments like Pancha rathas of Mahabalipuram, Inscriptions and Numismatics.
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Secondary source, as the term itself says that it is a secondly considered source. These sources are biased. Literary sources are considered as Secondary Sources.
Example:
Accounts of foreign travellers, Magazines and Religious literatures.
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