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One Space Or Two Spaces?

When I began writing technical documentation and courseware for Guru Labs, I asked a question during training about whether we should be putting two spaces after a period, colon, question mark and exclamation point, or one. The answer shocked me, as I was hoping for the standard answer as a means of teaching the rest of my colleagues. The answer was ONE space, not two. Then, I listened to the argument.

When the first commercially successful typewriter was invented by Christopher Latham Scholes in 1867 and sold to Remmington, each letter on the typebars were the same width. This is known today as a monospace font. Initially, rumor has it, that typists only put one space after the end of a sentence, question, or exclamation. However, in the early 1920s, we began to see additional spaces added, sometimes more than one, at the end of these punctuations. The "unwritten rule" was that two spaces were all that was needed, no more, and thus became the standard practice for published works.

This practice continued well into the age of computers, and was even taught in typing class (I was taught it too). However, computers have an advantage over typewriters- variable width font. In other words, the width of the letter "m" is different than the width for the letter "i". Due to these proportional fonts, we no longer need that extra space. In fact, we could easily say that the standard practice of putting extra spaces in our text is down right dead. Here are some reasons why you do not want an extra space:

  1. It is inefficient, requiring an extra keystroke for every sentence.
  2. Even if a program is set to automatically put an extra space after a period, such automation is never foolproof.
  3. There is no proof that an extra space actually improves readability.
  4. Two spaces are harder to control for than one in electronic documents.
  5. Two spaces can cause problems with line breaks in certain programs.

As an interesting side note, if you are an HTML developer, you must explicitly use the escape sequence for two spaces "  ", as HTML will ignore the extra space, and only place one in the rendered text.

Spend some time online Googling whether to use one space or two following sentences, and you will quickly see that the trend has reversed back to using a single space, not two. In the meeting with my coworkers, I was quickly humbled, and have since been using one space at the end of my fullstops instead of two. It was an easy habit to get into, and you should be doing the same.

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