Introduction

Footnotes and margin notes are essential for adding additional information and clarifications to a document without interrupting the flow of the main text. Footnotes are typically used to provide citations or definitions, while margin notes offer additional comments or insights. By mastering in using footnotes and margin notes, you can create documents that are both informative and engaging, without cluttering the main text with too much information.

Footnotes in LaTeX

In LaTeX, footnotes are a convenient way to provide additional information or references to the reader without interrupting the flow of the main text. Footnotes are typically placed at the bottom of the page and marked by a number or symbol in the main text. When the reader clicks on the number or symbol, they are taken to the corresponding footnote at the bottom of the page.

The \footnote command

LaTeX provides a simple command to create a footnote in your document:

\footnote{text}

The text that you want to appear in the footnote should be placed within the curly braces following the command.

Here's an example of how to use the \footnote command in LaTeX:

\documentclass{article}

\begin{document}

This is a sentence with a footnote\footnote{This is the text of the footnote}.

This is another sentence with a footnote\footnote{This is another footnote}.

\end{document}

This example generates the following output:

By default, the \footnote command in LaTeX generates footnote markers as sequential Arabic numerals starting from 1. However, you can manually set the value of the footnote marker by placing the desired number as an argument to the \footnote command:

\footnote[number]{text}

Here's an example:

\documentclass{article}

\begin{document}

This is a sentence with a footnote\footnote{This is the text of the footnote with automatically generated marker value.}. The marker value of this footnote is automatically generated.

This is another sentence with a footnote\footnote[10]{This is another footnote with a marker value assigned manually.}. The marker value of this footnote has been assigned manually.

This is another sentence with a footnote\footnote{This is another footnote with automatically generated marker value.}. The marker value of this footnote is also automatically generated. 

\end{document}

This example generates the following output:

The footnote marker value

In LaTeX, footnote markers are internally represented as a counter that is automatically incremented for each new footnote. The default footnote marker value is an Arabic numeral, starting from 1 for the first footnote and increasing by 1 for each subsequent footnote.

However, you can customize the appearance of the footnote marker by redefining the counter representation using commands such as \arabic, \roman, \alph, or \Alph.

Here's an example of customizing the appearance of the footnote marker by redefining the \thefootnote command:

\documentclass{article}
\usepackage{xcolor}

% Define a custom symbol for the footnote marker
\usepackage[symbol]{footmisc}
\makeatletter
\renewcommand{\thefootnote}{\textcolor{red}{\@Alph\c@footnote}}
\makeatother

\begin{document}

This is some text with a footnote.\footnote{Here is the text of the footnote.}

This is another footnote with a custom marker.\footnote{Here is the text of the second footnote.}

\end{document}

This example generates the following output:

Code Description:

• xcolor → This package is used to define a new color.
• \textcolor → This command is used to set the color of the marker.
• \makeatletter and \makeatother → These commands are used to allow the use of the @ symbol in the definition of \thefootnote, which is normally reserved for internal commands.
• \renewcommand{\thefootnote} → This command redefines the format of the footnote marker.
• \textcolor{red}{} → This command is used to change the color of the footnote marker to red.
• \@Alph → This command is used to typeset the counter in uppercase letters.
• \c@footnote → This command refers to the value of the footnote counter, which is automatically incremented each time a new footnote is added.

The effect of this code is to change the format of the footnote marker to use uppercase letters in red color.

Other LaTeX footnote commands

In addition to \footnote command with mentioned above, LaTeX provides the \footnotemark and \footnotetext commands which used to manually create a footnote reference mark and the corresponding footnote text, respectively.

The \footnotemark command → creates a reference mark in the main text at the current location. It takes no argument and increments the footnote counter by 1. The actual footnote text can be added later using the \footnotetext command. This can be useful in cases where you want to refer to the same footnote multiple times or when you want to place the footnote text at a different location than where the footnote marker appears in the text.

The \footnotetext command → is used to add text to a previously created footnote marker using \footnotemark.

Here are some more commonly used footnote commands in LaTeX:

Margin notes in LaTeX

Margin notes are a useful way to add extra information, comments, or reminders to a document. They are often used in academic writing, technical documentation, or any other kind of text where additional context or details can enhance the reader's understanding.

LaTeX provides several commands and packages for creating margin notes, including the built-in \marginpar command and the marginnote package. In this section, we will explore the usage and customization of these tools to create effective and visually appealing margin notes in your LaTeX documents.

The \marginpar command

The \marginpar command in LaTeX is used to create a margin note. It takes one required argument, which is the text of the margin note to be displayed inside the curly braces.

By default, the note is aligned with the right margin of the page where the command is used, but you can specify the side using optional arguments.

The general syntax of the \marginpar command is as follows:

\marginpar[left text]{right text}

Here, right text is the required argument and represents the text to be displayed in the margin. The optional argument left text represents the text to be displayed in the margin on the left side of the page. If you do not specify the optional argument, the margin note will be displayed on the right side of the page.

Here's an example of using marginpar command:

\documentclass{article}
\usepackage{lipsum} % for dummy text

\begin{document}

This is some text in the main body of the document.\lipsum[1] \marginpar{This is an example of margin note on the right side of document.}\lipsum[1]

\end{document}

This example generates the following output:

Reversing the position of margin notes

The \reversemarginpar and \normalmarginpar commands are used to switch the side of the margin where the margin note is displayed. By default, margin notes are displayed in the right margin in one-sided documents and in the outer margin in two-sided documents.

The \reversemarginpar command switches the margin note to the opposite side, while the \normalmarginpar command switches it back to the default side.

Here's an example usage of these commands:

\documentclass{article}
\usepackage{lipsum}

\begin{document}

\reversemarginpar
\marginpar{\textbf{Note:} In this example, the first margin note is displayed in the left margin due to the use of command \\reversemarginpar}

\lipsum[1]

\normalmarginpar
\marginpar{\textbf{Note:} The second margin note is displayed in the right margin due to the use of command \\normalmarginpar}

\lipsum[1]

\end{document}

This example generates the following output:

The marginnote package

The marginnote package provides an alternative to the standard LaTeX \marginpar command for producing margin notes. It offers additional functionality and customization options compared to the \marginpar command, including the ability to set the alignment of the margin note, adjust the spacing, and change the font style.

Here's an example of using the margin note package:

\documentclass{article}

\usepackage{marginnote} % for margin notes
\usepackage{lipsum} % for dummy text
\usepackage{xcolor} % for text color

\begin{document}

\section{Introduction}
\lipsum[1]\marginnote{\textcolor{red}{Note:} This is a margin note which shifted 8cm up the page.}[-8em]

\lipsum[2]\marginnote{\textcolor{orange}{Warning:} Another margin note.}\lipsum[1][1-6]

\subsection{Subsection}
\reversemarginpar\marginnote{\textbf{\textcolor{violet}{Tip:}} Margin note on left side.}\lipsum[1][1-6]

\end{document}

This example generates the following output: