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Programming: Continual Improvement
By an Amazon.com customer
The Pragmatic Programmer: From Journeyman to MasterThe Pragmatic Programmer: From Journeyman to Master by Andrew Hunt
Buy new: $32.25 / Used from: $21.00
Start here. End here, if you're in a rush... this is really the best source of information out there for being a better programmer.
Head First Design PatternsHead First Design Patterns by Elisabeth Freeman
Buy new: $29.67 / Used from: $24.00
Don't let the dippy format (or the Fisheye photo on the cover) steer you away from this important topic: if you are going to be a better programmer, you *must* know patterns, and this is a fine introduction. It's in Java, but the code is secondary to the abstract ideas they demonstrate: it is extensible to any language.
Refactoring: Improving the Design of Existing CodeRefactoring: Improving the Design of Existing Code by Martin Fowler
Buy new: $41.93 / Used from: $23.99
Expensive, yes, and really you will read this one and only flip to the first 1/4 of the book thereafter. But refactoring your code effectively is a paramount skill for better programming... and knowing what "smells" to look for is perhaps even more important.
The Art of Project Management (Theory in Practice (O'Reilly))The Art of Project Management (Theory in Practice (O'Reilly)) by Scott Berkun
Buy used from: $17.99
Not about programming, perhaps, but about being effective. This focuses (almost exclusively) on software development projects, so it's well worth your read, even if you aren't a manager, as you'll learn about time estimation, what to work on when, and how developers' time should be blocked to be most effective.