# [Tex/LaTex] Why are default LaTeX TOP and BOTTOM margins so big

formattingmarginsmemoir

In the question Why are default LaTeX margins so big?, it is explained very well why the side margins have the large size they have (compared to most Word processors): The smaller line width provides a better reading experience. What is explained less well is why the top and bottom margins have the extraordinary size they have. Suppose I want to print a book in A5 format using the code

\documentclass[twoside,a5paper]{memoir}

\usepackage{lipsum,microtype}

\begin{document}
\noindent\lipsum[1-22]
\end{document}


The result is seen below. The size of the side margins indeed makes the line width perfect for comfortable reading. But I do not see what justifies having the top and bottom margins account for almost half of the entire height of the page. Why are the top and bottom margins so big in the standard page settings?

%\documentclass[twoside,a5paper]{memoir}