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Literature for a Software Engineer
Concrete Mathematics: Foundation for Computer ScienceConcrete Mathematics: Foundation for Computer Science by Ronald L. Graham
Buy new: £46.81 / Used from: £31.99
Despite what you might think, it's all based upon maths. Unfortunately, perhaps.
The  C Programming Language (2nd Edition)The C Programming Language (2nd Edition) by Brian W. Kernighan
Buy new: £19.17 / Used from: £13.00
C is what low (not lowest) level programming is made of. Learn with its creators.
Expert C ProgrammingExpert C Programming by Peter van der Linden
Buy used from: £13.69
I'm told this is a good companion to the C Bible above. Never read it though.
Introduction to AlgorithmsIntroduction to Algorithms by Thomas H. Cormen
Buy new: £57.80 / Used from: £35.00
In order to write good software you need to be proficient with algorithm design and analysis.
The Art of Computer Programming: v. 1-3: Bd. 1: Fundamental Algorithms / Bd. 2: Seminumerical Algorithms / Bd. 3: Sorting and Searching: Vol 1-3 (Series in Computer Science & Information Processing)The Art of Computer Programming: v. 1-3: Bd. 1: Fundamental Algorithms / Bd. 2: Seminumerical Algorithms / Bd. 3: Sorting and Searching: Vol 1-3 (Series in Computer Science & Information Processing) by Donald E. Knuth
Buy new: £82.35 / Used from: £50.00
The Bible of algorithm theory. A massive three-volume masterpiece from Master Knuth.
Design patterns : elements of reusable object-oriented softwareDesign patterns : elements of reusable object-oriented software by Erich Gamma
Buy new: £25.16 / Used from: £17.50
Software should be well designed and this books teaches how to circumvent common pitfalls.
The Practice of Programming (Professional Computing)The Practice of Programming (Professional Computing) by Brian W. Kernighan
Buy new: £14.49 / Used from: £8.20
A good programming style should top a good design. This book teaches you the former.
CryptonomiconCryptonomicon by Neal Stephenson
Buy used from: £1.69
Now that you have the foundations, you can stop to catch your breath while reading a true geek book :)
The C++ Programming Language, Special EditionThe C++ Programming Language, Special Edition by Bjarne Stroustrup
Buy new: £27.46 / Used from: £20.19
C is not everything. C++ takes it to a different paradigm: Object-Oriented.
Java in a Nutshell (In a Nutshell (O'Reilly))Java in a Nutshell (In a Nutshell (O'Reilly)) by David Flanagan
Buy new: £25.65 / Used from: £2.26
This was my introduction to Java and honestly I can't recommend it high enough.
TCP/IP Network Administration: Help for UNIX System AdministratorsTCP/IP Network Administration: Help for UNIX System Administrators by Craig Hunt
Buy new: £20.43 / Used from: £14.23
This book has all you need to know about Unix-oriented network adminstration. Ok, maybe almost everything.
DNS and BINDDNS and BIND by Paul Albitz
Buy used from: £1.52
Definitely the best reference on DNS adminstration using BIND. Trust me on this one.
Computer NetworksComputer Networks by Andrew S. Tanenbaum
Buy used from: £52.00
This book covers networks from physical level to top level applications. A must.
Operating Systems: Design And Implementation (International Edition)Operating Systems: Design And Implementation (International Edition) by Andrew S. Tanenbaum
Buy used from: £19.00
A bit dated but arguably still the best reference on Operating System design.
The Design and Implementation of the 4.4 BSD Operating System (Addison-Wesley UNIX and Open Systems Series)The Design and Implementation of the 4.4 BSD Operating System (Addison-Wesley UNIX and Open Systems Series) by Marshall Kirk McKusick
Buy new: £39.09 / Used from: £20.26
The very best book to get acquainted with a particular OS implementation: the 4.4 BSD
Understanding the Linux KernelUnderstanding the Linux Kernel by Daniel Bovet
Buy used from: £4.22
If you want to learn about the guts of Linux, start here. And learn a bunch of cutting edge OS theory as you go along.
Compilers: Principles, Techniques and ToolsCompilers: Principles, Techniques and Tools by A.V. Aho
Buy used from: £7.96
Regarding compiler design, the so-called "Dragon Book" might be a decent introduction to a challenging subject.
The Gnu C Library Reference ManualThe Gnu C Library Reference Manual by Sandra Loosemore
A comprehensive guide to the Glibc written by the ones who really know the drill including McGrath and Drepper.
The ANSI Common Lisp Book (Prentice Hall Series in Artificial Intelligence)The ANSI Common Lisp Book (Prentice Hall Series in Artificial Intelligence) by Paul Graham
Buy new: £38.79 / Used from: £37.58
If you program in a higher level, Lisp is arguably the language of choice. This books is a perfect introduction to the ANSI Common Lisp dialect.
Stories of Your Life and OthersStories of Your Life and Others by Ted Chiang
Buy used from: £16.37
To end with a master's stroke here's the finest modern sci-fi by Ted Chiang.