1. A dispute, especially a public one, between sides holding opposing views.
2. The act or practice of engaging in such disputes: writers skilled at controversy.
For your discussion you should find at least three sources
Use information found during your research to back up your opinion.
From the Free Dictionary: http://www.thefreedictionary.com/
Don't forget to record your sources so they can be cited in your bibliography.
Always evaluate the credibility of web pages in particular, but all your sources generally.
Use the General Research page for citation builders.