I remember to have read few year ago1 that babel line2 should be placed at the end of the preamble in order to avoid problems with other packages. (I believe hyperref package should also be placed at the end of the preamble for the same reason.)
However, I see, in MWEs, the babel line often just after the \documentclass.
Is there any differences? What is the good practice here?
Addendum
Here is my LaTeX template. Do you see any other misplaced packages calls in general?
\documentclass[12pt,twoside,a4paper]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{setspace}
\usepackage{todonotes}
\usepackage{graphicx}
\usepackage{lmodern}
\usepackage{xspace}
\usepackage[style=authoryear-comp,hyperref,backend=biber,isbn=false,doi=false,url=false,date=year]{biblatex}
\AtEveryBibitem{\clearlist{language}}
\renewcommand*{\newunitpunct}{\addcomma\space}
\bibliography{biblio}
\title{}
\author{}
\usepackage[francais,english]{babel}
\usepackage{csquotes}
\usepackage[colorlinks]{hyperref}
\begin{document}
\maketitle
\tableofcontents
\onehalfspacing
\printbibliography
\end{document}
1. I don't remember where... Sorry.
2.\usepackage[dutch,english]{babel}
fontencandinputenc. – egreg Dec 20 '13 at 18:17