This is hard skills as opposed to soft skills - the things here are all relatively easy.
The idea is that to become talented, there are some skills which are "hard" skills - there's only one "right" way, and you have to get it right every single time if you want to be proficient in a skill. This idea comes from "The Little Book of Talent", which gives the example of playing the violin - placing your fingers correctly on the strings is a hard skill, interpreting the emotion of a piece is a soft skill (with different "right" approaches, allowing for creativity).
For programming, I figured that hard skills are all the basic operations. For someone used to programming, these aren't confusing, but you can program faster if you're not having to think about or look up whether string length is len(s), s.len, or s.length.
NB: The code here is rough-and-ready, not polished - I aimed for speed when writing it ;-)