added section about unnumbered subsections, escaping characters and landscape page

README.md

@@ -48,6 +48,9 @@ automatically styled correctly.
 | `\subsubsection{<YOUR_TITLE>}`    | This is the second subtitle. It is numbered with three numbers (e.g. 1.1.1 Subsubtitle).                   |
 | `\subsubsubsection{<YOUR_TITLE>}` | This is the third subtitle. It is not numbered at all and is also not showing up in the table of contents. |
 
+If the section should not be numbered, you can use a * before the opening bracket. Should look like this:
+`\subsection*{<YOUR_TITLE>}`.
+
 ## Formatting text
 
 The following commands are used to format normal paragraphs. However, most commands can be used in other environments (
@@ -60,6 +63,16 @@ e.g. tables) as well.
 | `\textit{<TEXT>}`    | Formats the text inside the brackets italic.                                                                                     |
 | `\underline{<TEXT>}` | Underlines the text inside the brackets.                                                                                         |
 
+## Escaping characters
+
+Some characters are used as a part of a command for latex. Due to that, they need to be escaped when they should be
+printed specifically. To escape a character, you use a '\\' before the character or symbol. Typical symbols you need to
+escape are:
+
+| Symbol | Escaped |
+|--------|---------|
+| \\     | \\\     |
+
 ## Bulletpoints and Enumerations
 
 ### Bulletpoints
@@ -232,3 +245,234 @@ The full table-definition defined with placeholders looks like this:
 Here, we also have the table captioned (which enables us to create a table-directory) and we also gave the table a
 label. The label is (as with graphics) important to reference it in the text, that it can be placed correctly by the
 compiler.
+
+# Reference tables and images in text
+
+With the compiler in LaTeX you get the best results with the placement of pictures and tables, if you reference them in
+the text they belong to. The compiler then places them near that text automatically. You can also reference to a
+section, in which case the title of the section gets automatically updated.
+
+## Referencing tables & images
+
+The process of referencing tables and images is the same for both of them. In the preceeding chapters of this manual we
+have seen the labelling process for tables and images.
+
+### Labelling tables & images
+
+To create a reference, the target-element has to be given an id first. That id is called label in LaTeX. Its best
+practice, to label tables and images differently. I personally like to use the following prefixes for tables and images,
+followed by a short 1-3 word description of the image or table.
+
+| type  | label                      |
+|-------|----------------------------|
+| Table | tab:<DESCRIPTION_OF_TABLE> |
+| Image | fig:<DESCRIPTION_OF_IMAGE> |
+
+```latex
+\begin{figure}
+    \centering
+    \includegraphics[width=\linewidth]{graphics/examplegraphic}
+    \label{fig:exampleimage}
+\end{figure}
+
+\begin{center}
+    \begin{tabularx}{\textwidth}{| m | m |}
+        \hline
+        \textbf{Header 1} & \textbf{Header 2} \\ \hline
+        Content 1.1       & Content 1.2       \\ \hline
+    \end{tabularx}
+    \label{tab:exampletable}
+\end{center}
+```
+
+### Referencing on tables & images in the text
+
+To reference on tables and images in the text, we use the command `cref`. It takes the label of the element you want to
+reference as a parameter. So an example-usage in a text would be the following:
+
+```latex
+This is a text example. You can see its usage in the image \cref{fig:exampleimage}.
+You can also view the table \cref{tab:exampletable} for the full command reference.
+```
+
+## Referencing sections
+
+Referencing sections works basically the same way as referencing tables or images. It also uses labels on the sections,
+but it does not use `cref` to create the reference. Instead we just use `ref`.
+
+### Labelling sections
+
+For labelling sections, I also like to use a prefix. I use the prefix `sec:` for sections. After the prefix, there is a
+short description of the section (or the whole title if it's just 1-3 words) to identify the section uniquely.
+
+| type     | label                        |
+|----------|------------------------------|
+| sections | sec:<DESCRIPTION_OF_SECTION> |
+
+```latex
+\section{This is a section.}
+\label{sec:examplesection} This is the text that is displayed directly after the title.
+```
+
+### Referencing a section in the text
+
+As mentioned, we reference a section similarly to tables and images. We just use another command to reference it. We use
+`\ref`, which takes the label of the section as an argument.
+
+```latex
+This is a text. In this text we reference to the chapter \ref{sec:examplesection}. 
+```
+
+# Citing with BibTeX
+
+This template is already setup to use citations with BibTeX. To define your sources to cite from, you need to use the
+`bibliography.bib` file.
+
+## Defining sources
+
+When defining sources, it's important to know, what type of source you want to create and cite.
+For mor information you can visit https://www.bibtex.com/e/entry-types/. There all BibTeX types are documented.
+
+### Defining Web-Sources
+
+To define web sources, I've found the type "misc" perfect. You can always use the following template and fill in the
+variables in with blanks.
+
+> It's **very important** to fill out the variable `<CITING_ID>`. This variable is used to reference the reference in
+> the
+> text to the correct BibTeX entry.
+
+```latex
+@misc{<CITING_ID>,
+author = {<AUTHOR_NAME>},
+title = {<WEBSITE_TITLE>},
+date = {<PUBLISHED_DATE>},
+year = {<PUBLISHED_YEAR>},
+urldate = {<VIEWED_ON_DATE>},
+note = {Abgerufen am <VIEWED_ON_DATE>},
+howpublished = {<URL_TO_PAGE>}
+}
+```
+
+### Defining a Book-Source
+
+To define a book source, it's basically the same principle as a web source. You just got other variables / fields to
+fill in.
+
+```latex
+@book{<CITING_ID>,
+author    = {<AUTHOR_NAME>},
+title     = {<BOOK_TITLE>},
+publisher = {<PUBLISHER>},
+year      = {<YEAR_PUBLISHED>},
+pages = {<PAGES_RELEVANT>}
+}
+```
+
+### Defining a Newspaper-Source
+
+Newspaper sources work the same. You got a few more variables to fill, because there are more informations relevant.
+
+```latex
+@article{<CITING_ID>,
+author   = {<AUTHOR_NAME>},
+title    = {<ARTICLE_TITLE>},
+journal  = {<NEWSPAPER_NAME>},
+year     = {<YEAR_PUBLISHED>},
+volume   = {<NEWSPAPER_VOLUME>},
+number   = {<NUMBER>},
+pages    = {<PAGES_OF_NEWSPAPER_RELEVANT>},
+}
+```
+
+## Citing defined sources in LaTeX
+
+To cite your sources you've defined in your bibliography file, you can use the syntax of `\cite{<CITING_ID>}` as you can
+see, you need your citing-id here again. This is to reference your citing in the text to the correct entry in your
+bibtex-file.
+
+# Importing other files
+
+With LaTeX you can import other files (such as other LaTeX files or pdfs) into your main file. This is very useful for
+attachments or external documents, which you want to include in your documentation.
+
+## Import .tex files
+
+To import .tex files, you can use `\input{<FILEPATH>}` or `\import{<FILEPATH>}`.
+
+## Import one .tex file
+
+To import a single text file, you can just use `\input{<FILEPATH>}`.
+
+## Import multiple .tex files after each other
+
+If you want to import multiple .tex files directly after each other, the syntax is a bit special. You use
+`\input{<FILEPATH>}` for the first .tex file, and `\import{<FILEPATH>}` for all the following .tex files. As soon as
+there is a text, heading or float (graphics/tables) between two imported .tex files, you can use `\input{<FILEPATH>}`
+again. See the example below for clarification.
+
+```latex
+\input{<FILEPATH_1>}
+\include{<FILEPATH_2>}
+\include{<FILEPATH_3>}
+\include{<FILEPATH_4>}
+
+
+\section{New header}
+This is a text for this header.
+
+\input{<FILEPATH_5>}
+```
+
+## Importing external pdf's
+
+Importing pdfs is especially interesting for attaching sources to your documentation. The most practical way is to use a
+special configuration of the `\includegraphics` command.
+
+```latex
+\includegraphics[height=0.9\textheight]{<PDF_FILEPATH>}
+```
+
+With this configuration you also have enough room to add a header above the included pdf.
+
+### Importing a selection of pdf pages
+
+There is a possibility to import only two pages of a pdf into your document. Use the following configuration for this:
+
+```latex
+\includepdf[pages={<PAGE_RANGE>}, noautoscale=true, scale=0.9, pagecommand={\thispagestyle{fancy}}]{<PDF_FILE_PATH>}
+```
+
+In page range its possible to use a number-range. To include from the first to for example 3rd page you can also use the
+keyword `first`. The same is possible with the last page by using the keyword `last`.
+
+### Importing the whole multipage pdf document
+
+To import a full pdf document with multiple pages, you need a combination of the above standing commands. This is
+because if you want to have a title above the first page, you need to make space for the title. With the
+`\includegraphics` command, we make that space by making the height of the float smaller.
+
+So to import multiple pages of the same document, use the following syntax:
+
+```latex
+\includegraphics[height=0.9\textheight]{<PDF_FILEPATH>}
+\includepdf[pages={2-last}, noautoscale=true, scale=0.9, pagecommand={\thispagestyle{fancy}}]{<PDF_FILEPATH>}
+```
+
+The first command imports the first page of your pdf. The second command includes the 2nd to last page into your main
+file. You can also change the page-range of the second command, in case you don't want all pages to the last inculded.
+
+# Create a landscape page inside a document
+
+To create a landscape page inside a portrait document, you can use `\begin{landscape}`. In the following example this is
+explained better:
+
+```latex
+This paragraph is still in portrait.
+\pagebreak
+\begin{landscape}
+  This paragraph is in landscape.
+\end{landscape}
+
+This paragraph is in portrait again.
+```