Copyscape mechanism debate

so i was just wondering about the way it works, right now i can't afford to go for copyscape search or ordering articles. so this thread will be useful for people who fall under this category.

i want to know from you all how copyscape actually figures out that a particular sentence or a paragraph is copied from somewhere else. im not talking about its script but ordering of words, how they do that ? i found smallseotools unreliable, i have checked it.

ok, lets start one by one, tell about your experience. please use examples. it will be good for newbies and people who will be rewriting articles for their first websites.

Copyscape itself isnt reliable but does a good job overall. It basically looks at exact word orders and percentage of shared phrases and sentences.

Beating copyscape is only useful for beating sites that openly sell unique content that is copyscape approved or something like that.
Google and the other search engines do not use copyscape or anything even remotely like it.
Getting copied content published or selling copied content are the only two reasons I can see to what to reverse engineer CS and most buyers/publishers no longer rely solely on CS anyway.

I buy from SEO generals and Iwriter and via Elancer and various other places. I certainly don't rely on the fact it's supposed to be CS passed - I don't know any serious content buyer or publisher that does.

Scritty