Q: Why reference?
A: To distinguish your ideas from those of others and acknowledge your sources. Also, to enable the reader to follow up if he/she is interested in the source you have used.
Q: What is the difference between a bibliography and a reference list?
A: Reference List, Works Cited, Literature Cited, Sources Cited, References, all of these terms refer to a list of sources actually cited throughout your work.
A: Bibliography, Bibliographical References, all of these terms refer to a list of sources that can be found at the end of your work in alphabetical order by the authors' last name. In some systems, this list may include books you have read, but you have not actually referred to. However, please check your institution's guidelines as it is not always permissable to include sources that have not been used in the text.
Q: What are endnotes and footnotes?
A: Footnotes are used to supplement your comments in the body of your essay. Inserted in numerical order automatically by your computer, they provide yet another opportunity to refer to other related and insightful material that might not necessarily be relevant to your essay at hand. Footnotes can be inserted at the bottom of the page or as their own page at the end (called endnotes).