There is a subtle but useful distinction between code and software. Programmers write code: a formal plan of the software, expressing its intent in maximal detail. Software is the end product: in execution it is what the user perceives, interacts with and experiences. Sometimes this difference can be significant.

Be careful not to confuse the map with the territory. Presentation and representation are different concepts for different purposes. The everyday notation for many quantities, such as money or time of day, is not necessarily a good indicator of how they should best be represented in a program.

We were in the pub when Charles posed an NP-hard problem: "How do you teach programmers style and elegance in code? I would like five points or properties that I can teach to my programmers." Trusty pints of Guinness in hand, Charles, Frank and I set about trying to find some kind of answer.