For me it was "Teach yourself...Assembler" - not because it was a great book or anything, but it was the first book I purchased to learn actual programming. I

For me it was "Teach yourself...Assembler" - not because it was a great book or anything, but it was the first book I purchased to learn actual programming. I don't think I even finished the book. (assembler is tedious and hard!) But it began a lifelong love of computers and software.