The Snows of Kilimanjaro (ed. by Odland S.) (based on a vocabulary of 1800 words) (на англ.яз.) Easy Readers ISBN 978-87-23-90228-3

And they know the same about spam, including the server names, mailer versions, and protocols. If I thought that I could keep up current rates of spam filtering, I would consider this problem solved. But it doesn't mean much to be able to filter out most present-day spam, because spam evolves. Indeed, most anti spam techniques so far have been like pesticides that do nothing more than create a new, resistant strain of bugs. I'm more hopeful about Bayesian filters, because they evolve with the spam. So as spammers start using v1agra instead of viagra to evade simple-minded spam filters based on individual words, Bayesian filters automatically notice. Indeed, v1agra is far more damning evidence than viagra, and Bayesian filters know precisely how much more. Still, anyone who proposes a plan for spam filtering has to be able to answer the question: if the spammers knew exactly what you were doing, how well could they get past you? For example, I think that if checksum-based spam filtering becomes a serious obstacle, the spammers will just switch to mad-lib techniques for generating message bodies ...»