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If you like (or need) textbooks as your way into a topic, you can do a lot worse than this. Lots of mediocre racy stuff gets written about this sector, but here it the nuts and bolts set out in short, accessible chapters in plain language. Not a riveting read but it does not pretend to do so. If you want to be entertained read something else, if you want to learn the easy way settle down with this great textbook which has been revised multiple times.