Studies on optimal code width?

Question

If you enable the \"View Right Margin\" in your IDE of choice, it is likely that it will default to 80 characters. I tend to change it to 120 for no reason other than it was th

Answer 1

Disregarding hardware restrictions, and any differences in how we read code versus natural language, I see three primary reasons to limit lines to around 80 characters.

1. Human eyeballs are round, not really narrow and wide, and most of their resolution is in the middle. When reading for hours at a time it is a lot more comfortable to sweep the eyes in short arcs, using one scroll bar as needed. I don't know of a formal study specific to the legibility of code, but from my own observations, with the monitor 2 feet away, with text sized at a 10pt monospaced font, 100 characters takes up about 1/3 of my horizontal field of vision, or around 60 degrees (outside of the 30 degrees or so where all our eyes' resolution is at).
2. Most people use a large monitor at work so that they can see multiple things without clicking back and forth, not so that they can see one thing really big.
3. Shorter lines contain less complexity, which hopefully forces a developer to break up make their code into more digestible units.