From this lessons, I learned the three types of sources Primary, Secondary, and Tertiary sources. 

•  Primary source is a material written or produced in the period that you may be investigating.

These are the first hand document of an event. there are a few primary sources such as diaries, letters, interview, journals, speeches and the last one is autobiography.

These are a few examples those picture

• Secondary source is something that is written about a primary source. these are a few example of secondary sources such as: bibliography, newspaper, journals, books, TV, Radio, and documentaries.

Tertiary source is consist of information which is a distillation and the collection of primary and secondary sources. the examples of tertiary sources such as: Bibliographies of bibliography, directories of directories, guides of literature.