But doing so costs money that may not be easy to find in departmental budgets. Instead of copying passages out of books and journals, students can simply pull up entire papers from the sites and paste chunks of text into their own word processors. Professors know that the sites are out there, but few have the time to search through them for evidence when they suspect a student of plagiarism.
Nobody has time to do it.
Plagiarism.org maintains a data base that it says is filled with works available from term-paper mills and elsewhere on the Web, as well as with papers submitted by professors. When a professor uploads a paper to the site, its computers try to match the paper with texts already included in the data base. Professors get back an originality report, which highlights parts of the text that may have been copied from other sources and also cites the source material. Professors can use their own judgment about whether material was plagiarized. The process is intended to detect not only a student who submits a paper entirely written by someone else, but also a student who turns in a paper composed of bits and pieces of different texts.