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What can the 5 worst typos in history teach you about the importance of proofreading?

Everyone makes mistakes from time to time, but in our increasingly online world, our blunders can have long-term consequences. The internet relishes a good fail compilation and unintended errors can spread like wildfire.

This means that the stakes for businesses that market themselves online are higher than ever.

So, read about five of the worst typos in history, and what they can teach you about the importance of proofreading and quality checks.

1. Thou shalt commit what? “The Sinners’ Bible” (1631)

One of the most infamous editions of the Bible – known as the “Wicked Bible”, “Sinners’ Bible” or “Adulterous Bible” – was published in London in 1631. The diabolical error? The omission of “not” from one of the 10 Commandments.

17th-century readers were shocked to read that, in fact, “thou shalt commit adultery”. The publisher released 1,000 erroneous versions before the issue was spotted a year later. The two men who ran the publishing house were summoned before King Charles I, stripped of their publishing licenses and fined almost £34,000 in today’s money.

While mistakes on your website, guides or newsletters are unlikely to get you dragged before the current King Charles, errors could cause confusion, compliance issues, and loss of trust and reputation.

To ensure such errors are caught, professional editors and proofreaders employ a range of techniques to deliver flawless copy, including using the Read Aloud function on Word, opting for dual monitors to read text on a bigger screen, and even reading text backwards from the end to the start.

2. Popeye the Sailor Con Man? (1870)

One small numerical error, made by a German chemist in 1870, created a nutritional myth that endures to this day.

Erich von Wolf was measuring the iron content of spinach when he put a decimal point in the wrong place, reporting that it contained 35 grams of iron instead of 3.5 – 10 times more iron than it actually did! The myth of spinach as an iron-rich superfood was born, and popularised by the spinach-fuelled Popeye the Sailorman comic strip and cartoons of the 1930s onwards.

Although the mistake was finally spotted in 1937, by that point it was too late and spinach’s reputation had been cemented in the public consciousness.

This example illustrates how unintended errors can take on a life of their own and, with so many companies using the internet to market their business, your errors could be preserved forever. Just imagine if your business featured in some future article about the worst typos in history…

That’s why it is crucial that you take time to check and recheck your work before it is published. Ideally, run your content by a second pair of eyes before any unintended errors escape into the wild.

3. Haunted by typos: Webster’s International Dictionary (1939)

Quiz time: what do the words “dord”, “phantomnation”, “cairbow” and “momblishness” have in common?

Answer: they are all completely made-up words that found their way into official dictionaries due to typos!

“Dord”, for example, was discovered in 1939 by an editor for Webster’s International Dictionary. They couldn’t find any origin for the term, but eventually deduced that it was mistakenly copied from an editor’s note that said, “D or d” – that is, “density” could be written with an uppercase “D” or lowercase “d”.

Even so, dord stuck around and appeared in copycat dictionaries for many years after. It now stands as a famous example of a “ghost word”.

This illustrates the importance of not assuming too much, but instead checking your sources, links, facts and figures, and claims to make sure that your business and its online reputation aren’t haunted by unintended clangers.

4. The most expensive hyphen in history: Nasa (1962)

On 2 July 1962, Nasa launched the unmanned Mariner 1 space probe to perform a flyby of Venus.

But in less than five minutes, the spacecraft had flown way off course and the control team had to blow it up, costing the US government around $80,000.

It turned out that the guidance software instructions were missing an overbar, similar to a hyphen, above the “R” symbol that represents the radius of a circle. This led to massive miscalculations and unexpected course corrections.

This disaster is a striking example of how even minute oversights can have devastating consequences, particularly when it comes to technical information.

No wonder that science-fiction author Arthur C. Clarke called it “the most expensive hyphen in history”.

5. Let me just googol that… : Stanford University (1997)

In 1997, Larry Page and Sean Anderson were at Stanford University with some fellow students brainstorming names for a massive data-index website. Anderson suggested “googolplex” – one of the largest describable numbers – but Page shortened it to “googol”.

Anderson made a typing error when checking if the domain name was available, and came up with “google” by accident. Page liked this version better, so they registered the site immediately.

On this occasion, turning an unintended typo into a brand worked incredibly well, but of course, you need to know how to do things correctly before you can start breaking the rules. That’s why you should employ the services of professional copywriters and proofreaders to ensure your business’s reputation is protected and your content makes the impression you intended.

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