I've been looking at publishers' websites and noticed that some publishers like their submissions in Times New Roman and some of them like Courier. Is there a reason why they prefer these different fonts, or is it just a personal thing from publisher to publisher?One reason is that all computers (PC and Mac) have these two fonts, making it easy to convert files. Sometimes when a document is opened on a computer that doesn't have the font it was written in, it can go all skeewampus.
The other reason has to do with estimating final page count.
Courier is a fixed-width font, meaning all letters take the same amount of space. It gives you a uniform number of spaces per page making it easier (according to some) to estimate a final page count.
I prefer Times, however, because it is easier to read. I haven't found that it's any more difficult to estimate page count from Times.