The two most common citation styles are MLA and Chicago. A "Works Cited" page is associated with the MLA style, while the Chicago style is associated with a bibliography. For MLA citations, you need all the pertinent information from your source; here is an example with MLA Works Cited citations:
Author. Title of Work. Location of publication: Publishing house, year published. Medium of Publication (Print).
For a website, it depends on what the website is. If it's just an article on a regular webpage, use this:
Author (last name, first name). Title (italics for an individual work, in quotes if it's part of a larger work). Website title. Date of publication. Medium of publication (Web). Date of access.
If it's an article from a scholarly journal:
Author. "Title of article." Title of Journal Edition # (Year): page numbers. Medium of publication (Web). Date of access.
If it's an article in an online website database use this:
Author. "Title of article." Name of Periodical Series#/name Volume# Issue#: page numbers. Title of database. Medium of publication (Web). Date of access.
Basically, each citation has many details that are meant to include every bit of relevant information about the source you use so that another person can find the exact source and information you found.