I'm writing a document in LaTeX, using the package setspace with the onehalfspacing setting.
I'm satisfied with the space between two lines of text, but I can't find a way to start a new paragraph leaving only one blank line: if I leave a blank line in the code, the output starts a new paragraph without leaving a vertical space between the two lines of text; if I use \\ and then leave an empty line in the code, the resulting output presents itself with too much space between the lines of text. Unfortunately, answers to similar questions posted here didn't solve my problem.
Summarising, I want to know how I can leave just an empty line in the pdf output when I start a new paragraph. Can anyone help me?
Edit: I found useful for my purpose this page Lengths and when to use them, posted by Runar Trollet in the accepted answer. This solved my problem. In order to start a new paragraph it's enough to leave a blank line in the code. This will result in output as a carriage return with the new line indented and no vertical space between lines - to be precise, no more than the normal space between them. If you want to leave some space between the end of a paragraph and the start of a new one, just use the commands \smallskip, \medskip or \bigskip before leaving the empty line in the code.

\\(it doesn't work) always leave a blank line, the spacing between paragraphs is set using the\parskiplength (or use theparskippackage to set it for you) – David Carlisle Sep 12 '16 at 11:22\parskipset and have a problem in some cases, make an example of that problem and ask about that. – David Carlisle Sep 12 '16 at 12:23