Ask HN: What is the most career altering course or book you have gone through?

Thinking, Fast and Slow by psychologist Daniel Kahneman.

With special mentions to K&R

"The C Programming Language", by Kernighan and Ritchie.

Code: The Hidden Language of Computer Hardware And Software by Charles Petzold.

Fantastic book.

"The Annotated Turing" - I didn't know you could meaningfully intertwine biography and technical analysis like that.

An amazing book.

How Will You Measure Your Life? by Clayton Christensen.

"Head First Series"

as well as The Manager’s Path.

The Bible.

Creativity, Inc.

Database Design for Mere Mortals. The first afternoon I spent reading and puzzling through that book was worth an entire semester of computer science classes on the topic — and caused me to fall in love with relational databases.

Programming Perl, 1st Ed. from Larry Wall.