leave spaces or not

What is an M- or an N- dash if I may ask?

BelieverHi,

When you are using M-dashes or the other dash (if you have time to expand your explantion to cover the N-dash too), do you have to leave spaces in front of it or behind it, or don't have to leave any?

I'm not familiar with m-dashes or n-dashes.

They are dashes of different length. Anyway, it seems like a kinda technical question, and I think that on Internet it's full of dissertation about this topic. For example, try going for that:
http:

Sorry, I didn't address the initial question (about the spaces). Anyway, I was reading on wikipedia and I found some answer:

According to most American sources (e.g., http://en.wikipedia.org/wiki/The_Chicago_Manual_of_Style) and to some British sources (e.g.,

An em-dash or M-dash is this: —

I do prefer to leave at least a little space around it because it just looks "funny" to me without them. You can use them as a sudden break in your thought — hey, do you have anything to eat? Or the way you might use a colon — that is, to give a little more explanation. You can also use it to set off parenthetical information — you know, information that's

@ Grammar Geek: thank you very much for this great explanation It really helped a lot......