Special Characters In Latex

LaTeX Font Sizes, Families, and Styles

This document provides an overview of how to control font sizes, families, and styles in LaTeX. Understanding these commands is crucial for creating well-formatted and visually appealing documents.

Note: The visual representation of LaTeX commands below is approximated using standard HTML/CSS for demonstration purposes. The exact rendering in a compiled LaTeX document may differ slightly.

---

1. Font Sizes

LaTeX provides a set of predefined commands for changing font sizes. These commands affect the font size from the point they are declared until the end of the current group (e.g., inside an environment like \section{} or within curly braces {}).

1.1. Absolute Font Size Commands

These commands offer a relative scaling based on the base font size of the document (which is typically 10pt, 11pt, or 12pt, set in the \documentclass command).

Command	Description	Approximate Size Relative to Base	Example
\tiny	Smallest available font size.	~5-6pt (for 10pt base)	Example of \tiny text.
\scriptsize	Slightly larger than tiny, often used for footnotes.	~7pt (for 10pt base)	Example of \scriptsize text.
\footnotesize	Commonly used for footnotes and captions.	~8pt (for 10pt base)	Example of \footnotesize text.
\small	Slightly smaller than the document's base font size.	~9pt (for 10pt base)	Example of \small text.
\normalsize	Resets to the document's base font size.	Base font size (e.g., 10pt)	Example of \normalsize text.
\large	Slightly larger than the document's base font size.	~12pt (for 10pt base)	Example of \large text.
\Large	Even larger.	~14.4pt (for 10pt base)	Example of \Large text.
\LARGE	Significantly larger.	~17.28pt (for 10pt base)	Example of \LARGE text.
\huge	Very large.	~20.74pt (for 10pt base)	Example of \huge text.
\Huge	Largest standard font size.	~24.88pt (for 10pt base)	Example of \Huge text.

1.2. Example Usage of Font Sizes

\documentclass[11pt]{article}
\begin{document}
This is \normalsize normal text.

{\small This is small text.}

\section*{Font Size Demonstrations}
\Huge This is Huge.
\large This is large text.
\normalsize Back to normal size.
\tiny This is tiny text.
\end{document}

1.3. Custom Font Sizes with fontspec (XeLaTeX/LuaLaTeX)

For more precise control over font sizes (and to use system fonts), you can use the fontspec package with XeLaTeX or LuaLaTeX compilers. The \fontsize{size}{line-spacing} command followed by \selectfont allows for custom sizes.

\documentclass{article}
\usepackage{fontspec} % Requires XeLaTeX or LuaLaTeX

\begin{document}
Normal text.

\fontsize{18pt}{20pt}\selectfont This text is 18pt with 20pt line spacing.

\fontsize{8mm}{10mm}\selectfont This text is 8mm with 10mm line spacing.

\normalsize Back to normal.
\end{document}

---

2. Font Families

LaTeX typically defaults to the Computer Modern font family. You can change the font family for your document or specific parts of it.

2.1. Standard Font Families

LaTeX provides three basic font families:

Command	Description	Example
\rmfamily or \textrm{...}	Roman (Serif) font - the default for most documents.	Example of Roman (\rmfamily) text.
\sffamily or \textsf{...}	Sans-serif font - without serifs.	Example of Sans-serif (\sffamily) text.
\ttfamily or \texttt{...}	Typewriter (Monospace) font - fixed-width, like a typewriter.	Example of Typewriter (\ttfamily) text.

2.2. Example Usage of Font Families

\documentclass{article}
\begin{document}
This is normal \rmfamily Roman text.

{\sffamily This is sans-serif text.}

This is back to Roman.

\texttt{This is typewriter text, useful for code.}
\end{document}

2.3. Using External Font Packages

Many packages are available to use different font families. Some popular ones include:

• \usepackage{lmodern}: Latin Modern, an enhanced version of Computer Modern.
• \usepackage{mathptmx}: Times Roman for text and mathematics.
• \usepackage{helvet}: Helvetica for sans-serif.
• \usepackage{courier}: Courier for monospace.
• \usepackage{palatino}: Palatino for text.

\documentclass{article}
\usepackage{mathptmx} % Use Times Roman
\usepackage{helvet}   % Use Helvetica for sans-serif
\usepackage{courier}  % Use Courier for monospace

\begin{document}
This document now uses \rmfamily Times Roman as the default.

\sffamily This is Helvetica sans-serif text.

\texttt{And this is Courier monospace text.}
\end{document}

2.4. Custom Fonts with fontspec (XeLaTeX/LuaLaTeX)

The fontspec package allows you to use any font installed on your system. This offers unparalleled flexibility.

\documentclass{article}
\usepackage{fontspec} % Requires XeLaTeX or LuaLaTeX

\setmainfont{Times New Roman}
\setsansfont{Arial}
\setmonofont{Consolas}

\begin{document}
This is the main text in Times New Roman.

\textsf{This text is in Arial sans-serif.}

\texttt{This text is in Consolas monospace.}
\end{document}

---

3. Font Styles

Font styles refer to variations like bold, italic, slanted, small caps, etc.

3.1. Standard Font Style Commands

LaTeX provides several commands for applying different styles:

Command	Description	Example
\bfseries or \textbf{...}	Bold font.	Example of Bold (\bfseries) text.
\itshape or \textit{...}	Italic font.	Example of Italic (\itshape) text.
\slshape or \textsl{...}	Slanted font (similar to italic but often less cursive).	Example of Slanted (\slshape) text.
\scshape or \textsc{...}	Small Capitals font (uppercase characters with the height of lowercase ones).	Example of Small Capitals (\scshape) text.
\upshape or \textup{...}	Upright font (resets to normal from italic/slanted).	Example of Upright (\upshape) text.
\mdseries or \textmd{...}	Medium (normal) weight font (resets from bold).	Example of Medium (\mdseries) text.
\normalfont	Resets all font attributes (size, family, style) to the default.	Example of \normalfont text.

3.2. Example Usage of Font Styles

\documentclass{article}
\begin{document}
This is \normalfont normal text.

This is {\bfseries bold text}.

\textit{This is italic text.}

Here is some \textsl{slanted text}.

\textsc{This is small caps text}.

{\bfseries\itshape This is bold and italic.}

\normalfont Back to normal.
\end{document}

3.3. Combining Styles and Families

You can combine font styles with font families. For instance, you might want bold sans-serif text.

\documentclass{article}
\usepackage{helvet} % For sans-serif

\begin{document}
\textbf{Bold Roman text.}

\sffamily\textbf{Bold sans-serif text.}

\ttfamily\textit{Italic typewriter text.}

\sffamily\textsc{Small caps sans-serif text.}
\end{document}

---

4. Important Considerations

• Grouping: Most font commands are *declarations* and affect everything that follows until the end of the current group (delimited by curly braces {}). The \text...{} commands, however, act on their argument only.
• Compiler: Using system fonts or advanced font features requires XeLaTeX or LuaLaTeX compilers and the fontspec package. Standard LaTeX (pdfLaTeX) has more limited font capabilities.
• Font Availability: Not all font families support all styles (e.g., some fonts might not have a distinct slanted shape or small caps). LaTeX will try to approximate, but the results might not be ideal.
• Math Fonts: Changing text fonts does not automatically change math fonts. Special packages (like mathptmx, fourier, or unicode-math with XeLaTeX/LuaLaTeX) are needed to manage math fonts.

This document should serve as a practical guide for managing fonts in your LaTeX documents.