Clean Code

It walks you through DRY, KISS, and YAGNI with side-by-side examples of violations and refactored versions, mostly in Java. The naming conventions section is genuinely helpful, covering everything from why "d" is a terrible variable name to why booleans should start with is/has/can. The function design guidance keeps it practical, like keeping methods small and maintaining a single level of abstraction. Use this when you're refactoring messy code or doing code reviews. It won't teach you advanced patterns, but it will stop you from writing the kind of code that makes your teammates groan.