In general, primary sources for historical research include:
Reports written by eye-witnesses at the time of an event.
Other information compiled during the time period you are researching.
Primary research in history often involves systematic browsing in files of letters, reading pages and pages of an old diary, scanning months worth of local newspapers for reports on events. Much of this material is not indexed and not quickly available. Remember to budget the time needed to do this sort of research.
Other disciplines have different criteria for identifying primary sources. What is considered a primary source depends on the subject you’re working in. If you're still in doubt, ask your professor.
The primary sources of history are documents written by those who participated in or witnessed the event you’re studying. From very early periods there may be only a few surviving documents which are contemporary or nearly contemporary with the event in question.
For studies in social history, scholars also use administrative documents and contemporary literature.
For a dissertation or a paper meant for publication, scholars generally prefer to use the original documents.
For undergraduate papers, you can usually use modern edited and printed editions of books and documents which would not otherwise be available to you. Check with your instructor.
Among the types of documents which may be considered primary sources for history are:
Letters and diaries of participants or witnesses. These are often private recollections, meant to be read only by the observer or one or two friends. The most valuable of these sources are those which were written as close to the time of the event as possible.
Memoirs and autobiographies. These may have been meant as public documents, or may have been written to be shared with friends and family. They may have been written some years after the event you’re interested in and may represent the writer’s rationalizations or attempts to make a coherent narrative out of the events.
Interviews, speeches, memos written at the time. These are likely to be more public documents and may be less revealing.
Tapes and transcripts of Oral History sessions. These are often the only way in which the memories of older members of communities have been preserved. They can be especially important sources of information from Indigenous communities.
Newspaper reports or books and articles published at the time. These were often written by journalists or writers who were not personally involved. They may include interviews with, or recollections of, participants.
Records of an organization. The minutes of meetings, correspondence and other papers of an organization document the business of the group.
Government and church records. Censuses, court records, birth, death, marriage and burial records are important sources of information for social and demographic history.
Literature. The fiction, plays and poetry of a period can reflect common attitudes and beliefs of the time. These sources are used cautiously by social historians.
Sound and visual recordings. Where these are available, they can be valuable sources of information both for events and as documents reflecting the social life and customs of the last century and a half.
Artifacts. Buildings, tools, clothing, toys, furniture and other household items can all reveal aspects of the lives of the people who made and used them. Contemporary paintings and drawings can also be used to show how clothing was worn, how artifacts were used, and how people wished to be represented.