Not sure what exactly plagiarism is? Click on these pages to learn more:

• Plagiarism: What it is and how to recognize and avoid it : http://www.indiana.edu/~wts/pamphlets/plagiarism.shtml

This website offers examples of proper paraphrasing and explains what falls under "common knowledge". From Indiana University.

• Avoiding Plagiarism : http://owl.english.purdue.edu/handouts/research/r_plagiar.html

This tutorial from the Purdue University Online Writing Lab tells what types of information researchers need to cite in their papers and offers some practice exercises to test your knowledge of what plagiarism is.