Information comes in many formats, including digital files, books and magazines, video and audio downloads, interviews, and even concrete objects. In the broadest sense, information is anything that you take in using your five senses.
Primary: a firsthand source of information is original or first-person information. It can come from someone’s journal, from original scientific research, or from writers talking about their work on YouTube. Research articles from databases and websites are primary sources, as are conversations you have with your friends.
Secondary: a secondhand source of information is material that has been taken from primary sources and then synthesized, such as a book in which all the writer interviews are gathered together by the interviewer and published. A college textbook is another example of secondary information, since it synthesizes material taken from original sources.
Popular: material is written for the general public, whether as a book, article or website. The author doesn’t usually offer any proof for his/her opinion. Popular material can be written by journalists, celebrities or someone interested in the subject.
Scholarly: material is usually written by an expert with professional credentials, and contains facts, proofs, research, and citations which show how the author came to his/her conclusions.