Why are odd pages left pages?

Question

I'm typesetting a friend's novel using LaTeX (in my actual document I'm using memoir, but the same happens if I just use book). It's possible I'm going crazy, but I'm sure that it's setting up odd pages to be left pages, instead of right pages (which is what appears to be standard). My code looks something like this:

\documentclass{book}

\usepackage{lipsum}

\title{Lorem Ipsum Dolor Sit Amet}
\author{The Author}

\begin{document}
\frontmatter
\maketitle
\mainmatter

\lipsum

\end{document}

This generates me a 4 page PDF (you can download it here) - which I think has odd pages as left-hand pages (odd pages have wide right margins, even pages have wide left margins, but then on the other hand, odd pages have page numbers on the right hand side, which makes them look like right-hand pages).

Shouldn't I have a wide left margin? Have I totally misunderstood odd and even pages? Have I just completely lost it from staring at this for too long?

Answer 1

Odd pages come on right. The wider margin is the outer one, so on page one, you should have a wide right margin. So it seems to be correct.

The reason is that the outer margins should visually be the same as the "inner one", and the "inner one" is sum of the "inner margins" of both facing pages.