@zemichi @lambadalambda Word processing.
Some say the two spaces after a full stop was a typewriter hack to make up for lack of proper justification (look up the linotype process sometime). Others point out that it was Irish monks who gave us spaces between letters (and the ability to silently read) in the first place. Beforethemwordswerejustallruntogetherandyouhadtosoundthemout. No, really.
I point out that doublespacing is useful context in latex or vim.
@JollyOrc @zemichi @lambadalambda Sure, but HTML would be an excellent example of a case where the /entered/ text has absolutely no effect on the rendered /output/. So long as tokens are separated by one /or more/ whitespace elements, they're individuated. You can insert a thousand linefeeds, if you want, or a single space and no linefeeds at all. If you want /rendered/ whitespace, you specify that through formatting, structured input, or <pre>.