}
```
* Packages provide additional commands and functionalities.
* There are different packages for different use cases (e. g., mathematical formulas, lists, ...).
* Before they can be used, they have to be included **within the preamble.**
@slide(layout=content-only)
@title
Encoding
@content
``` {.lang-tex .hljs}
\usepackage[utf8]{inputenc}
\usepackage[t1]{fontenc}
```
* ++ The character encoding determines which characters are available.
* ++ **ASCII** contains no special characters like German umlauts.
* ++ **UTF-8** is a universal encoding.
@slide(layout=content-only)
@title
Language
@content
``` {.lang-tex .hljs}
\usepackage[ngerman]{babel}
```
* The package **`babel`** provides language-specific information (e. g., hyphenation, special characters, font changes, translated labels like ‘chapter,’ ‘table of contents’ or ‘figure’).
* **`ngerman`** is the German new spelling.
@slide(layout=wide-content)
@title
Languages
@content
A document can use multiple languages at once:
``` {.lang-tex .hljs}
\usepackage[ngerman, swedish, russian, greek, english]{babel}
```
To switch languages:
``` {.lang-tex .hljs}
\selectlanguage{}
\selectlanguage{}
```
Embedded Text in another language:
``` {.lang-tex .hljs}
\selectlanguage{}
\foreignlanguage{}{Text of language B in a Text of language A}
```
@slide(layout=content-and-preview)
@title
Languages — an example
@content
``` {.lang-tex .hljs}
\today
\selectlanguage{ngerman}
\today
\selectlanguage{swedish}
\today
\selectlanguage{russian}
\today
\selectlanguage{greek}
\today
\selectlanguage{english}
\today
```
@preview

@slide(layout=content-and-preview)
@title
Continuous Text
@content
``` {.lang-tex .hljs}
Continous text can be written directly ↲
in the source code. ↲
Simple line breaks ↲
are ignored, ↲
just as multiple space characters. ↲
↲
An empty line creates a new paragraph ↲
which has an indentation by default. ↲
Manual line breaks can be forced ↲
using two backslashes, but this use ↲
is strongly discouraged \\ ↲
within continuous text.
```
@preview

@slide(layout=content-and-preview-with-category)
@category
Caution!
@title
Reserved characters
@content
Some characters do things in LaTeX:
`# $ % ^ & _ { } ~ \`
``` {.lang-tex .hljs}
50% is one half.
```
Solution: prefix with ‘`\`’:
``` {.lang-tex .hljs}
50\% is one half.
```
Does not work for ‘`\\`’, use `\textbackslash` instead.
@preview

@slide(layout=content-and-preview)
@title
Sections and chapters
@content
Texts are structured by beeing subdivided in sections and chapters. Always available:
``` {.lang-tex .hljs}
\section{Level 1}
\subsection{Level 2}
\subsubsection{Level 3}
\paragraph{Level 4}
\subparagraph{Level 5}
```
Additionally, for some document classes:
``` {.lang-tex .hljs}
\chapter{Chapter}
\part{Part}
```
@preview

@slide(layout=content-and-preview)
@title
Sections and chapters
@content
With an asterisk, there is no numbering and no entry in the table of contents:
``` {.lang-tex .hljs}
\section*{No entry in table of contents}
```
You can also provide an alternative title for the table of contents:
``` {.lang-tex .hljs}
\section[Entry in table of contents]
{Actual chapter heading}
```
@preview

@slide(layout=wide-content)
@title
Front matter
@content
``` {.lang-tex .hljs data-source=title.tex}
\title{The World of Truffles}
\author{Fooboar Rüssel \and Fachschaft WIAI}
\date{\today}
\begin{document}
\maketitle
\end{document}
```
* The values for the entries are stored in the preamble.
* `\maketitle` typesets the front matter within the document environment.
* The exact appearance depends on the document class.
* Multiple authors can be joined with `\and`.
* If no date is given, the current date will be used. A different date can be defined with `\date{}`.
@slide(layout=content-and-preview)
@title
Front matter
@content
``` {.lang-tex .hljs data-source=title.tex}
\documentclass{article}
\usepackage{babel}
\title{The World of Truffles}
\author{Fooboar Rüssel
\and Fachschaft WIAI}
\date{\today}
\begin{document}
\maketitle
\section{Truffle hunt}
\subsection{Hunt with a pig}
\subsection{Hunt without a pig}
Why would you do that?
\section{Truffle recipes}
My favorite recipe
\end{document}
```
@preview

@slide(layout=content-only)
@title
Registers
@content
``` {.lang-tex .hljs}
\tableofcontents
\listoffigures
\listoftables
```
* automatic numbering
* elements with an asterisk (`*`) are hidden from the register: e. g. `\section*{}`.
* **generally requires two rounds of compilation**
@slide(layout=content-and-preview)
@title
Table of contents
@content
``` {.lang-tex .hljs data-source=title.tex}
\documentclass{article}
\usepackage{babel}
\begin{document}
\tableofcontents
\section{Truffle hunt}
The first section.
\subsection{Hunt with a pig}
A subsection.
\subsection{Hunt without a pig}
Another subsection.
\subsubsection[But why?]
{Why would you do that?}
Sub-subsection.
\section{Truffle recipes}
My favorite recipe
\end{document}
```
@preview

@slide(layout=wide-task)
@task-number
3
@title
Structure your document and text
@content
* Open the file `document-structure.tex`. It is located in the directory `exercises/basic-document-structure`.
* Wrap the entire text in a **document** environment and insert the following **preamble**. Compile the document.
``` {.lang-tex .hljs .fragment}
\documentclass{scrartcl}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[english]{babel}
```
* As you may already have noticed, **paragraphs** are marked as ‘`\\`’. Use real paragraphs instead.
* Time to structure our document! Use LaTex commands to declare all **headings** (`\section`, `\subsubsection`, etc.).
* Add a **table of contents** to your document.
@slide(layout=content-only)
@title
Before we can continue …
@content
Finally, **comment out** the preamble, the document environment, and the table of contents.
Only this way, your solution can be embedded in the script itself. (In TeXstudio, comments can be achieved by the shortcut Strg + T.)
We will learn in the following chapter why this is the case.