En or Em...erm

One thing that really separates the men from the boys in the world of punctuation, is the wrong use of a dash.

A good graphic designer knows the difference between an En dash and a Hyphen and when to use them. It is astonishing to see professional design groups turning out work where hyphens are used all over the place. Maybe they don't think it matters – but it does.

Definitions first; Hyphens, En and Em dashes are punctuation marks. Demonstrating them online is going to make life tricky, because web browsers don't really care about dashes, and although there is correct HTML mark up for ensuring your dashes do what they are supposed to do, not all browsers agree. So until the browser war is won, or lost, or ignored, using them can cause odd bits of code to appear instead. Wikipedia has a listing and offers up the various bits of code required.

Below shows correct usage:
Hyphen: a short ‘dash’ used to show a break in a word as it goes onto another line, or to join two words together, like black-cab. It is a minus sign, that is why it sits next door to the plus sign on the keyboard.

En dash: a dash (sometimes called an En rule) is one en in length, usually the width of the letter 'N' in the typeface you are using.

Em dash: another dash, one em long, the width of the letter 'M' in the typeface you are using. The actual length is governed by the point size you are using.

Confused? Don’t blame you. It is tricky because, in the first instance we are dealing with relative sizes. A millimeter is a millimeter, even in space, but, like the ‘x-height’ of any given typeface, the perceivable size varies. You notice this when you change a large chunk of text from one font to another, the document changes length. En and Em sizes change with the font, but it doesn't matter, it's all relative.

Usage
There is confusion around the correct usage of an en dash as opposed to an em dash. But there is absolutely no confusion about when not to use a hyphen.

Hyphen usage: A hyphen is a joining character, it joins words together like 'e-mail' or is used to show the join between the a broken word that has been pushed onto the next line, because the whole word will not fit on. You see this a lot in newspapers.
On the keyboard: A minus symbol

En dash usage: is used to show a range, or transition. There should be no spaces either side of it. For example 'The address of the pub is 22–24 Gin Lane.'
On the keyboard: option+hyphen

Spaced En Dash: is used in the same way as an Em dash (see below), and this is where a drop of confusion lies, strictly speaking, you should use a Em dash, but tastes and fashion change – even in punctuation – and the majority of stickler editors ask for a Spaced En dash, rather than Em dash, like so; 'you must use a spaced En dash – like so – or the Editor will moan'.

Em dash usage: is used to show a pause, a bit like a comma, but longer. Like this; I went down the pub – I always do when I want to discuss punctuation.
On the keyboard: option+shift+hyphen



You wouldn't think there was such a hoo-ha about using dashes, would you!