Before you begin studying history, you should become familiar with some of the characteristics that make history unique compared to other areas of study. unlike other disciplines, where the data or information that provides knowledge is available and easily observable, it is usually to observe the subject matter of history directly because, by definition, historical events . therefore, knowledge of historical events can be obtained only through the study and appraisal of various sources, such as documents, photographs, and eyewitness testimonies.

The process to study each subject is different from one another because of the difference in the sources, methods, and area of study. But what makes history different as a subject on how one extracts information from the sources. While in other subjects one can data is directly accessible that provides knowledge, in history, one has to look for the critical evaluation of the sources of data, the conditions in which the data was produced, the possibility of the written influence from his environment, etc. Therefore while studying history we the data collection process should be carefully opted.