The appearance of the English translation of the book on cybernetics makes the author feel additional responsibility. This is because literature on cyberne­ tics written in this language is quite voluminous. It contains books by renowned authorities on the subject such as N. Wiener, W. R. Ashby, G. Shannon, G. Wal­ter, and numerous popular-science books, to name the works of J. Murphy, D. Fink, A. M. Andrew, A. Cote as the most noteworthy.And still the author does not hesitate to present his book to the reader because many chapters of the book tell of Soviet achievements in cybernetics and compu­ ter technology, and they, as is well known, are formidable. People interested in the achievements of Soviet specialists following their original ways in various fields of cybernetics would do well 1o learn of them from this book.The book, moreover, differs appreciably from numerous other books on this subject. It was the intention of the author to write an easily understandable popular-science book which would contain some amusing, or even humouristic, elements and, at the same time, abide by the principle of an encyclopaedia in the alphabetical arrangement and in a serious and scientifically correct exposi­ tion of the subject matter.This, naturally, was no easy task.Three books had to be combined in one so that one could be read, the other looked over, the third used as a manual.The first consists of short stories about the wonderful and the unusual in cyber­ netics. The second—of detailed drawings. Just look at them and you’ll see eve­ rything in a nut-shell. You will be amazed, too, I hope, by the cartoons at the end of each story the ideas for which have been suggested by cartoonists from all over the world.The third book is the encyclopaedia from A to Z. Read it as you please: in the alphabetical order, or any letter you choose first; whichever way you read it the main concepts of cybernetics will be revealed to you. For each letter is inde­ pendent of the rest. Combined, they tell a concerted tale of the new science.Only the most important “letters” of the vast “letter store” of the cybernetics “ABC” have been chosen for this book. It was absolutely impossible to includeall the “letters”.The list of terms and objects described in the Automatics and Electronics En­cyclopaedia for specialists alone takes 100 pages of print, the encyclopaedia it­ self consisting of four great volumes of 500 pages each. Even the word list for the projected small cybernetics dictionary (note the word “small”) fills 30 pages of compact text.The principal words in this encyclopaedia are chosen so as to enable you to go over its pages from the simple to the more sophisticated without destroying the order of cybernetic “letters”.Translated from the Russian by M. Samokhvalov.