A citation is a shorthand way of referring to an information source. Citations are also called references. Research articles and conference papers (as well as other sources such as dissertations and many books) have - at the end - a list of citations that the author referred to. Citations consist of all the information required so anyone could track down the full text of that particular source. There are many different "styles" for writing citations. These styles dictate the order and formatting elements such as the title, publication year, volume, issue, authors, etc.
Articles, conference papers, and books found online (in an electronic format) are not considered websites and should not be cited as if they are websites.