I was wrong, 80 characters is fine

Do you remember when I said, in my 2019 post Why 80?, that “80 characters per line is a particular convention out of many that we know literally nothing about the benefit or cost of, even today”?

Today I saw a “rule of 66 non-white space characters per line” mentioned in connection with TeX. I couldn’t find that reference in the TeXbook, though it’s also in Bringhurst’s “The Elements of Typographic Style” so let’s go with it for the moment.

If there should be 66 non-white space characters per line, then a line should be 66 * (average word length + 1) / (average word length) characters long to hold 66 non-white space characters, on average, if it’s displaying a run of words. In English, the average word length is about five. That gives us 79.2 characters per line.

If you’re reading English, an 80 column terminal makes sense, if Bringhurst’s justification (pardon the pun) is valid. Though I still don’t know why people suggest 72 characters for commit message lines.

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5 Responses to I was wrong, 80 characters is fine

  1. Derek Jones says:

    Stuff happens, numbers get selected and stay with us, like the width of railroad tracks.

    People want to contribute and repeat the recommendations they know. A network effect is at play.

    Which computing related magic numbers, that have been handed to us by history, would you claim have an effective cost/benefit analysis?

  2. Graham says:

    Generally, not many. As an example 8-bit bytes (great for BCD, which is rarely done any more) has no practical benefit, on the other hand clearly 640kiB of RAM did turn out to be enough for anybody. However, in this case there is a probably-coincidental and almost certainly retrospective justification for 80 characters. Maybe not particularly compelling for 80 over 72, but certainly when comparing against other standards that exist or have existed, like 40 and 132 characters.

    BTW in the UK there are multiple railway gauges all in parallel (pardon the pun) use, while standard gauge is the most common there are others and even different loading gauges on standard gauge tracks. Network Rail’s loading gauge is smaller than the Berne gauge used in the rest of Europe, making British trains more expensive than European trains even though they’re smaller. This shows that eventually the cost/benefit analysis for the popular or standard number tips toward that number, for no other reason than that it’s popular.

  3. Fabian says:

    I believe 72 characters is an atavism which dates back to punched cards, where the first 72 characters where the actual data and the remaining 8 characters encoded the sequence in a line.

  4. Rene Kita says:

    Usenet articles and emails are traditionally wrapped at 72 characters. This is to allow multiple levels of quoting where each level will add a quote character to a line. I’m not sure why exactly 72, but it’s far away enough from 80 to allow multiple quotes.

    Patches from git were originally send via email and discussed on mailing lists, keeping the commit message at 72 characters allows the same amount of quoting as any other email.

  5. Pingback: Links 07/09/2023: LibreOffice 7.5.6 and Plans for LibrePlanet 2024 Have Begun | Techrights

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