Dear all,

I was thinking about posing to mathoverflow a question designed to collect the various typesetting conventions that lead to more professional looking LaTeX output, given that most mathematicians (such as myself) did not have any formal training in typesetting. The type of conventions I had in mind were things like the following:

* Use \langle, \rangle instead of <,> for inner products
* use \ll, \gg instead of <<, >>
* use \lvert, \rvert for absolute values, and \lVert, \rVert for norms
* use \mid instead of | for the "divides" symbol
* Use \operatorname for various operators such as Hom, End, etc.
* Use \colon when declaring domain and range of functions, e.g. f \colon X \to Y
* Use \dots instead of \cdots, \ldots for most ranges
* Use -- instead of - for page ranges and for joint authors (e.g. Cauchy--Schwarz)
* etc.

Also I wanted to collect not only the conventions themselves, but the justifications for them. For some of the conventions above, for instance, I can see why they are preferable to the alternatives, but for others all I know is that professional typesetters seem to all agree on the rule. But I am not sure whether this question is actually appropriate for MathOverflow as it is (a) not a mathematical question, and (b) would be a big list or community wiki rather than a question with a definite answer (unless, perhaps, someone provides a link to a style guide that has all of these sorts of things, but I have not been able to find a definitive such guide in my own searches). So I was wondering what other users felt about such a question.

The answer to almost all of them is "spacing".

I don't think that as asked the question is a good fit for the SE network (to be clear, I'm thinking about its fitness for TeX-SX, I don't think it would work in any way on MO). I think that the best strategy would be to set out to write a blog post about this and to ask specific questions when you find that you aren't able to figure something out for yourself. A lot is in the AMS guides, and more in standard typographical references.

Regarding what the actual differences are (there's some information as to why as well), here are some questions on TeX-SX where you could start reading.

• Use \langle, \rangle instead of <,> for inner products
  Difference between \langle and <
• use \ll, \gg instead of <<, >>
  How can I get double angle brackets, i.e. - << >>
• use \lvert, \rvert for absolute values, and \lVert, \rVert for norms
  \mid, |, \vert, \lvert, \rvert
• use \mid instead of | for the "divides" symbol
  \mid, |, \vert, \lvert, \rvert
• Use \operatorname for various operators such as Hom, End, etc.
  What's the difference between \mathrm and \operatorname?
• Use \colon when declaring domain and range of functions, e.g. f \colon X \to Y
  Using \colon or : in formulas?
• Use \dots instead of \cdots, \ldots for most ranges
  How to type the three dots in a product?
• Use -- instead of - for page ranges and for joint authors (e.g. Cauchy--Schwarz)
  Dashes: - vs. – vs. —