She started with defining the difference between Original or Derivative Sources, whether the information in a source is primary or secondary information, and whether the information answers the research question (direct evidence) or can be paired with other information to answer the question (indirect evidence). She showed wonder images that helped explain the concepts.
She also talked about the informant and that sources can have more than on informant. For example, the death certificate has the doctor as the informant about the illness and cause of death, while the genealogical information is usually given by a family member. (For more information on this subject, go here).
She spoke about conflicting evidence and how it is important to keep track of all of the evidence that you find and to write about why you think the evidence is conflicting. This is for yourself as well as for future researchers.
Lastly she spoke about source citations. These help show your research path and will enable a future researcher to find the sources you used.
Corey's informative presentation, with the many examples she used, made what could be a very dry subject, very entertaining. She was a wonderful speaker.
Good reference books she showed were:
Professional Genealogy: a Manual for Researchers, Writers, Editors, Lecturers, and Librarians edited by Elizabeth Shown Mills. Baltimore: Genealogical Publishing Company, 2001.
The BCG Genealogical Stands Manual. Board for Certification of Genealogists, Prove, Utah: Ancestry Publishing, 2000.
Evidence Explained, Citing History Sources from Artifacts to Cyberspace, by Elizabeth Shown Mills. Baltimore: Genealogical Publishing Company, 2009.