Q. What is the proper spacing BETWEEN paragraphs? Is it the “space” connected with the font size?
A. In documents published in print, there is usually no extra space between paragraphs. So the space between the last line of one paragraph and the beginning of the next is exactly the same as the space between any two lines of text within a paragraph. For single-spacing this is typically a couple of points more than the font size. New paragraphs are identified by a first-line indent alone.
In documents published online, where space isn’t limited by page size and paper costs, the more common approach (and the typical default in HTML) is to allow the equivalent of a blank line (or a bit less than that) between paragraphs but no first-line indent. If you’re preparing a manuscript for publication or for a class paper, paragraph indents are still the norm; if you use them, then you can set extra space between paragraphs to zero. For more on this topic, see our Shop Talk post on paragraphing in manuscripts; if you’re a student, be sure to check out our paper-formatting Tip Sheets.