For those of you who didn’t know it, London taxis are called black cabs. But what’s the difference between a black-cab driver and a black cab driver? Answer: the taxi driver is either just another driver of a black cab or a taxi driver who happens to be black. The hyphen makes all the difference.
A hyphen indicates that two or more words are made into one. It is a great tool for avoiding misunderstandings.
Another example: a real-time waster is not necessarily the same as a real time waster.
The hyphen can also make a sentence easier to read, for example when used as an adjective modifying a noun:
This is up-to-date information
But the hyphens are not needed when the sentence is structured the other way around, with no noun following the adjective:
This information is up to date
A lot of writers make mistakes when using hyphens and often it doesn’t matter. But, as I just mentioned, sometimes a hyphen or a lack thereof can make a big difference to the understanding of a sentence.
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