Types of Plagiarism
The writer turns in another's work, word-for-word, as his or her own.
The writer copies significant portions of text straight from a single source, without alteration.
The writer tries to disguise plagiarism by copying from several different sources, tweaking the sentences to make them fit together while retaining most of the original phrasing.
Although the writer has retained the essential content of the source, he or she has altered the paper's appearance slightly by changing key words and phrases.
The writer takes the time to paraphrase most of the paper from other sources and make it all fit together, instead of spending the same effort on original work.
The writer "borrows" generously from his or her previous work, violating policies concerning the expectation of originality adopted by most academic institutions.
A special thanks to Plagiarism.org for allowing me to post this section from their site.