A really good overview of the field of CS is _Great Principles of Computing_ by Peter Denning and Craig Martell, 2015. It's a good book for CS students who want overviews of less familiar areas of computer science, and for anyone (in other areas) who want to know more about computation. Another is Subrata Dasgupta's _Computer Science: A Very Short Introduction_, a 2016 addition to Oxford's Very Short Introduction series. It has over five pages of further references to more detailed and specialized works.
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