I used the HP48 family of calculators for most high school and college science classes, so it was easy to keep track of units throughout the entire chain of cal

I used the HP48 family of calculators for most high school and college science classes, so it was easy to keep track of units throughout the entire chain of calculations with automatic conversions and a degree of type checking (not quite fully automatic dimensional analysis). I developed a very strong habit of always being explicit about units for any quantity, and was appalled at how lenient many students and instructors were. Worst were the textbooks that defined obscure domain-specific constants without explicitly stating the units, often forcing the reader to reference several pages to be sure of the units in use for that context.