Why do printers print 132 columns on 14 7/8″ paper? It’s history #VintageComputing @kenshirriff @IBM
You may have a printout from a printer with you now, characters forming lines of up to 132 characters, fitting on paper that is 14 7/8″ wide. But why that many characters and that wide a paper? Ken Shirriff (@kenshirriff) does the historical work to find out:
After researching this question, I’ve concluded that there are two answers. The first answer is that there isn’t anything special about 132 columns. In particular, early printers used an astoundingly large variety of line widths including 50, 55, 60, 70, 73, 80, 88, 89, 92, 100, 118, 120, 128, 130, 136, 140, 144, 150 and 160 characters. This shows there was no strong technical or business reason to use 132 columns. Instead, 132 columns became a de facto standard due to the popularity of the IBM 1401 computer and its high-performance 1403 line printer, which happened to print 132 columns.
The first printer to use 132 columns appears to be the IBM 1403 line printer, which provided output for the IBM 1401 business computer. The IBM 1401 was the most popular computer of the early 1960s, largely due to its low price…. the IBM 1401 could be rented for $2500 per month, opening up the market to medium-sized businesses that used it for payroll, inventory, accounting and many other business tasks. As a result, over 10,000 IBM 1401 computers were in use by the mid-1960s.
Because the IBM 1403 printer was so popular, its 132-column format became a de facto standard, supported by later printers and terminals for backward compatibility. The 14 7/8″×11″ green-bar paper that it used and remains popular to this day, available at office supply stores.
Ok, so due to the likes of IBM we have 132 characters as a “standard” – but how did it get to 132? and what about the 14 7/8 inches for the paper?
Well, we won’t spoil repeating Ken’s hard work, but it involves machines back from the 19th and the first half of the 20th century. Great work Ken!
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