Such sources include, among other things, diaries, letters, newspapers, magazine articles, tape recordings, pictures, and maps. Such material may have appeared in print before, edited or unedited, and still be a source. The term is meant to be restrictive rather than inclusive, in that it attempts to indicate that works of secondary scholarship, or synthesis, are not sources, since the data have been distilled by another person. One good way for the novice historian to lose Brownie points among his serious-minded fellows is to call a biography of George Washington or an analysis of the Magna Charta a 'source'. A primary source gives the words of the witnesses or the first recorders of an event.
Secondary sources are 'descriptions of the event derived from and based on primary sources'.
The line between primary and secondary sources is often indistinct, for example, a single document may be a primary source on some matter and a secondary source on others. The researcher, using a number of such primary sources, produces a secondary source . The historical information portrayed in these timelines reflect over a year of research poring over several hundred textbooks and encyclopedias, just to obtain successions of ancient rulers. The first timeline produced, The Timeline of Ancient Egypt, began with a 5 foot roll of chart paper with scattered pharaohs and dates, just so I could visualize the reigns of the pharaohs over 3,000 years. The Encyclopedia Britannica was my first source.