2.16 The Preamble
The preamble is the part of the source code that comes
after the \documentclass
command and before
\begin{document} (the start of the
document environment). Only
a few
special commands may be placed in the preamble (such as \title), and there are a few
special commands that may only go in the preamble (such as \usepackage).
Nothing that generates text (for example, \maketitle) may go in the preamble.
\documentclass{...}
⬅ This bit here is the preamble
\begin{document}
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