Why Two Spaces Followed the Typewriter
The extra space after a period was a practical convention in the age of the typewriter. Its keys advanced the carriage by the same amount whether they typed a narrow letter such as “i” or a wide one such as “m.” Because every character occupied a fixed-width slot, typists often added a second space after a sentence to make its end easier to spot.
That habit carried into typing classes and office style guides, even as the tools changed. It was a workaround for the typewriter’s rigid spacing, not a requirement of English punctuation.
Modern Fonts Do the Spacing Differently
Most digital text uses proportional fonts, in which letters take up different amounts of room. Typesetting also adjusts the space around punctuation, so a period already creates a visible pause. Adding another full space can make that gap look oversized, especially in a narrow column or a block of justified text, where uneven spacing may stand out even more.
A single space is the usual convention in modern publishing and digital writing. The old double-space habit still appears because it was taught for decades, but today it can make a paragraph look as if its sentences are drifting apart—an artifact of a machine people no longer use.
