Using min where I mean max and max where I mean min is my favorite classic mistake that I usually just make most of the time and remember to check for and fix a

Using min where I mean max and max where I mean min is my favorite classic mistake that I usually just make most of the time and remember to check for and fix afterwards. The same thing with misusing "this" in JavaScript closures: no matter how hard I try to consciously avoid doing it, it's always the first thing I check for when code doesn't work as intended, because I still make that same mistake all the time. Another source of confusion in code that Ben Shneiderman pointed out, is that the meaning of "and" and "or" are opposite to programmers and normal human beings, so languages like SQL and logical expressions in most programming languages are fundamentally confusing to many people, and the inconsistency can be an un-obvious blind spot. Normal humans mean to union when they say "this AND that AND those AND these", while programmers mean to intersect when they say "this AND that AND those AND these". So that's a terrible source of confusion. In other words, programmers think adding "AND" clauses narrows down the selection like "((user.age >= 18) AND (user.gender = 'F'))", while humans think adding "AND" clauses augments the selection like "adults AND women". I'm not advocating changing the meaning of "AND" and "OR", just pointing out that it's a source of confusion you should look out for, and be aware of when talking with non-programmers. I saw Alvy Ray Smith give a talk about 3D graphics programming, and he confessed that he and his colleagues would just write some code and then flip the signs around until it did what they meant it to do. That made me feel a lot less embarrassed about doing that myself.