23.2 Line Length
Line lengths should not exceed 80 characters.45
This is a typical recommendation for many programming language style guides because it makes it easier to lay out text edit windows side by side and to view the code on the web without wrapping, easier to view diffs from version control, etc. About the only thing that is sacrificed is laying out expressions on a single line.
Even 80 characters may be too many for rendering in print; for instance, in this manual, the number of code characters that fit on a line is about 65.↩