On 22 Apr 2009, at 2:53 am, Richard Kelsall wrote:
Dusan Kolar wrote: ...
Or is the reason much deeper? Or, is the bound set to 78 characters just because it is as good number as any other? ... As a little historical detour I think the 80 character limit goes back to 1928 when IBM designed their punched card format
Interestingly enough, IBM also made 96-column cards. But the one time I had to use them, I found that the keypunch didn't actually print all 96 columns. It may be worth noting that the era of 80-column keypunches was also the era of 132-column printers. DEC terminals used to have a 132-column mode, and some terminal emulators still offer you an 80/132 choice. Poking around on the web, I found http://www.svendtofte.com/code/max_width_in_ie/ from which the rest of this message is a quote. (The original has links.) --------------------------------------------------------- There has been several studies, on the topic of on line line-lengths, one of the better was done by the department of psychology at Wichita State University, entitled "The Effects of Line Length on Children and Adults' Online Reading Performance", and it clearly shows, in many different situations, and under different speed requirements, how people read on-line. More on the subject can be found in the company Human Factors Internationals' newsletter, " Reading Text Online". While from reading these articles, you get the clear image, that there are no firm rules, but only vague ideas, and "maybe this is best". But still, some conclusions are drawn by the researchers: From this study, as well as the studies mentioned above, it is suggested that full-screen line length should be avoided for on-line documents, especially if a large amount of text is presented. For adults, it is suggested that medium line lengths should be presented (approximately 65 to 75 CPL). Children, on the other hand, indicated their preference for the narrowest line length (45 CPL) and, thus, it may be beneficial to use narrow line lengths when possible. The emphasis added are mine. Further, we can also discern, that a good reading width, should be around 60 CPL (characters per line).