In my discipline? I guess

Write code that's easy to update without breaking dependent code.

That'll save the ancient programmers of the 1950's some time.

If I were trying to build up programming from scratch, it'd get pretty hairy.

Build a machine that, when "x = 1.1; while (10. - x*x > .0001) x = x - ((x * x - 10.) / (10.*x)); display x" is entered into it, displays a value close to the ratio of the longest side of a right triangle to another side expressed as the sum of 0 or 1 times the lengths of successive bisections.