Paragraphs are separated by at least one empty line. If you need to enforce a line break within a paragraph, use \\ at the end of a line.

To preserve the line breaks, indentation and blank lines in a region, but otherwise use normal formatting, you can use this construct, which can also be used to format poetry.

#+BEGIN_VERSE
 Great clouds overhead
 Tiny black birds rise and fall
 Snow covers Emacs

    ---AlexSchroeder
#+END_VERSE

When quoting a passage from another document, it is customary to format this as a paragraph that is indented on both the left and the right margin. You can include quotations in Org documents like this:

#+BEGIN_QUOTE
Everything should be made as simple as possible,
but not any simpler ---Albert Einstein
#+END_QUOTE

If you would like to center some text, do it like this:

#+BEGIN_CENTER
Everything should be made as simple as possible, \\
but not any simpler
#+END_CENTER

You can make words *bold*, /italic/, _underlined_, =verbatim= and ~code~, and, if you must, +strike-through+. Text in the code and verbatim string is not processed for Org specific syntax; it is exported verbatim. Org provides a single command as entry point for inserting the marker character.

C-c C-x C-f (org-emphasize)

Prompt for a marker character and insert or change an emphasis. If there is an active region, change that region to a new emphasis. If there is no region, just insert the marker characters and position the cursor between them.

To turn off fontification for marked up text, you can set org-fontify-emphasized-text to nil. To narrow down the list of the fontified markup syntax, you can customize ~org-emphasis-alist~(note: The markup will still be recognized. Just not highlighted visually in Emacs.).

To hide the emphasis markup characters in your buffers, set org-hide-emphasis-markers to t.

Sometimes, when marked text also contains the marker character itself, the result may be unsettling. For example,

/One may expect this whole sentence to be italicized, but the
following ~user/?variable~ contains =/= character, which effectively
stops emphasis there./

You can use zero width space to help Org sorting out the ambiguity. See Escape Character for more details.

^ and _ are used to indicate super- and subscripts. To increase the readability of ASCII text, it is not necessary, but OK, to surround multi-character sub- and superscripts with curly braces. For example

The radius of the sun is R_sun = 6.96 x 10^8 m.  On the other hand,
the radius of Alpha Centauri is R_{Alpha Centauri} = 1.28 x R_{sun}.

If you write a text where the underscore is often used in a different context, Org's convention to always interpret these as subscripts can get in your way. Configure the variable org-use-sub-superscripts and/or org-export-with-sub-superscripts to change this convention. For example, when setting these variables to {}, a_b is not displayed/exported(note: The underlying markup still remains a sub/superscript. Only the visual display and export behavior changes.) as a subscript, but a_{b} is.

You can set both org-use-sub-superscripts org-export-with-sub-superscripts in a file using the export option ^: (see Export Settings). For example, #+OPTIONS: ^:{} sets the two options to {} and limits super- and subscripts to the curly bracket notation.

You can also toggle the visual display of super- and subscripts:

C-c C-x \ (org-toggle-pretty-entities)

This command formats sub- and superscripts in a WYSIWYM way.

Set both org-pretty-entities and org-pretty-entities-include-sub-superscripts to t to start with super- and subscripts visually interpreted as specified by the option org-use-sub-superscripts.

You can use LaTeX-like syntax to insert special symbols—named entities—like \alpha to indicate the Greek letter, or \to to indicate an arrow. Completion for these symbols is available, just type \ and maybe a few letters, and press M-TAB to see possible completions. If you need such a symbol inside a word, terminate it with a pair of curly brackets. For example

Pro tip: Given a circle \Gamma of diameter d, the length of its
circumference is \pi{}d.

A large number of entities is provided, with names taken from both HTML and LaTeX; you can comfortably browse the complete list from a dedicated buffer using the command org-entities-help. It is also possible to provide your own special symbols in the variable org-entities-user.

During export, these symbols are transformed into the native format of the exporter backend. Strings like \alpha are exported as α in the HTML output, and as \(\alpha\) in the LaTeX output. Similarly, \nbsp becomes   in HTML and ~ in LaTeX.

If you would like to see entities displayed as UTF-8 characters, use the following command(note: You can turn this on by default by setting the variable org-pretty-entities, or on a per-file basis with the STARTUP option entitiespretty.):

C-c C-x \ (org-toggle-pretty-entities)

Toggle display of entities as UTF-8 characters. This does not change the buffer content which remains plain ASCII, but it overlays the UTF-8 character for display purposes only.

In addition to regular entities defined above, Org exports in a special way(note: This behavior can be disabled with - export setting (see Export Settings).) the following commonly used character combinations: \- is treated as a shy hyphen, -- and --- are converted into dashes, and ... becomes a compact set of dots.

Plain ASCII is normally sufficient for almost all note-taking. Exceptions include scientific notes, which often require mathematical

symbols and the occasional formula. LaTeX³⁷ is widely used to typeset scientific documents. Org mode supports embedding LaTeX code into its files, because many academics are used to writing and reading LaTeX source code, and because it can be readily processed to produce pretty output for a number of export backends.

\begin{equation}                        % arbitrary environments,
x=\sqrt{b}                              % even tables, figures, etc
\end{equation}

If $a^2=b$ and \( b=2 \), then the solution must be
either $$ a=+\sqrt{2} $$ or \[ a=-\sqrt{2} \].

#+STARTUP: latexpreview

#+STARTUP: nolatexpreview

(add-hook 'org-mode-hook #'turn-on-org-cdlatex)

You can include literal examples that should not be subjected to markup. Such examples are typeset in monospace, so this is well suited for source code and similar examples.

#+BEGIN_EXAMPLE
  Some example from a text file.
#+END_EXAMPLE

There is one limitation, however. You must insert a comma right before lines starting with either *, ,*, #+ or ,#+, as those may be interpreted as outlines nodes or some other special syntax. Org transparently strips these additional commas whenever it accesses the contents of the block.

#+BEGIN_EXAMPLE
,* I am no real headline
#+END_EXAMPLE

For simplicity when using small examples, you can also start the example lines with a colon followed by a space. There may also be additional whitespace before the colon:

Here is an example
   : Some example from a text file.

If the example is source code from a programming language, or any other text that can be marked up by Font Lock in Emacs, you can ask

for the example to look like the fontified Emacs buffer⁴⁰. This is done with the code block, where you also need to specify the name

of the major mode that should be used to fontify the example⁴¹, see Structure Templates for shortcuts to easily insert code blocks.

#+BEGIN_SRC emacs-lisp
  (defun org-xor (a b)
    "Exclusive or."
    (if a (not b) b))
#+END_SRC

Both in example and in src snippets, you can add a -n switch to the #+BEGIN line(note: In the src snippets, switches must be placed right after the language name and before the header arguments), to get the lines of the example numbered. The -n takes an optional numeric argument specifying the starting line number of the block. If you use a +n switch, the numbering from the previous numbered snippet is continued in the current one. The +n switch can also take a numeric argument. This adds the value of the argument to the last line of the previous block to determine the starting line number.

#+BEGIN_SRC emacs-lisp -n 20
  ;; This exports with line number 20.
  (message "This is line 21")
#+END_SRC

#+BEGIN_SRC emacs-lisp +n 10
  ;; This is listed as line 31.
  (message "This is line 32")
#+END_SRC

In literal examples, Org interprets strings like (ref:name) as labels, and use them as targets for special hyperlinks like [[#_0028name_0029][(name)]]—i.e., the reference name enclosed in single parentheses. In HTML, hovering the mouse over such a link remote-highlights the corresponding code line(note: This requires some JavaScript which is not automatically included in the HTML output: you have to customize the variable org-html-head-include-scripts to t to have it included (it is nil by default).), which is kind of cool.

You can also add a -r switch which removes the labels from the source code(note: Adding -k to -n -r keeps the labels in the source code while using line numbers for the links, which might be useful to explain those in an Org mode example code.). With the -n switch, links to these references are labeled by the line numbers from the code listing. Otherwise, links use the labels with no parentheses. Here is an example:

#+BEGIN_SRC emacs-lisp -n -r
  (save-excursion                 (ref:sc)
     (goto-char (point-min))      (ref:jump)
#+END_SRC
In line [[#_0028sc_0029][(sc)]] we remember the current position. [[#_0028jump_0029][Line (jump)]]
jumps to point-min.

Source code and examples may be indented in order to align nicely with the surrounding text, and in particular with plain list structure (see Plain Lists). By default, Org only retains the relative indentation between lines, e.g., when exporting the contents of the block. However, you can use the -i switch to also preserve the global indentation, if it does matter. See Editing Source Code.

If the syntax for the label format conflicts with the language syntax, use a -l switch to change the format, for example

#+BEGIN_SRC pascal -n -r -l "((%s))"

See also the variable org-coderef-label-format.

HTML export also allows examples to be published as text areas (see Text areas in HTML export).

Because the #+BEGIN … #+END patterns need to be added so often, a shortcut is provided (see Structure Templates).

C-c ' (org-edit-special)

Edit the source code example at point in its native mode. This works by switching to a temporary buffer with the source code. You need to exit by pressing C-c ' again. The edited version then replaces the old version in the Org buffer. Fixed-width regions—where each line starts with a colon followed by a space—are edited using Artist mode(note: You may select a different mode with the variable org-edit-fixed-width-region-mode.) to allow creating ASCII drawings easily. Using this command in an empty line creates a new fixed-width region.

Calling org-store-link (see Handling Links) while editing a source code example in a temporary buffer created with C-c ' prompts for a label. Make sure that it is unique in the current buffer, and insert it with the proper formatting like (ref:label) at the end of the current line. Then the label is stored as a link (label), for retrieval with C-c C-l.

Org mode can display previews of hyperlinks (see Hyperlinks) inside Org buffers. By default, only image links(note: Image links are file: and attachment: links to existing image files; Emacs can only display the linked images listed in image-types variable) can be previewed inline, where the images are displayed in place of the link path.

You can customize the previews as described in Adding Hyperlink preview. Link previews do not have to display images – any kind of display decoration (see Overlay Properties) can be used.

You can preview the supported link types in the whole buffer, in the current section, active region or at point with the following commands:

C-c C-x C-v (org-link-preview)

Create inline previews for external links in the active region, if any; the link at point, if there is such; or in the current section otherwise. With a prefix argument, clear link previews at point or in the current entry. With a double prefix argument, preview all links in the buffer. With triple prefix argument, hide previews for all links in the buffer.

By default, only links without descriptions are previewed. You can force displaying previews for all supported links (including links with descriptions) using a numeric argument of 1. This will toggle all previews in the active region, the link at point or the current section. A numeric prefix argument of 11 will toggle previews in the whole buffer instead.

Org mode can display link previews automatically when opening buffers. Either customize org-startup-with-link-previews or use the #+STARTUP: linkpreviews keyword to enable previews for that specific buffer when opening it. #+STARTUP: nolinkpreviews will disable previews on startup in the buffer.

C-c C-x C-M-v (org-link-preview-refresh)

Assure inline display of external link previews in the whole buffer and refresh them.

M-x org-link-preview-region

Create inline previews for external links in the active region, or the buffer. With a prefix argument, also preview links with a text description part.

M-x org-link-preview-clear

Clear external link previews in the active region, or the buffer.

Link previews can also be displayed when cycling the folding state. When the custom option org-cycle-link-previews-display is set, supported link types under the subtree (including images) will be displayed automatically.

./img/cat.jpg

#+CAPTION: This is the caption for the next figure link (or table)
#+NAME:   fig:SED-HR4049
[[#_002e_002fimg_002fa_002ejpg][./img/a.jpg]]

#+ATTR_HTML: :align center

#+ATTR_HTML: :align right
#+ATTR_ORG: :align center
[[/path/to/image/file.png]]

You can assign a caption to a specific part of a document by inserting a CAPTION keyword immediately before it:

#+CAPTION: This is the caption for the next table (or link)
| ... | ... |
|-----+-----|

Optionally, the caption can take the form:

#+CAPTION[Short caption]: Longer caption.

Even though images and tables are prominent examples of captioned structures, the same caption mechanism can apply to many others—e.g., LaTeX equations, source code blocks. Depending on the export backend, those may or may not be handled.

A line consisting of only dashes, and at least 5 of them, is exported as a horizontal line.

A footnote is started by a footnote marker in square brackets in column 0, no indentation allowed. It ends at the next footnote definition, headline, or after two consecutive empty lines. The footnote reference is simply the marker in square brackets, inside text. Markers always start with fn:. For example:

The Org website[fn:1] now looks a lot better than it used to.
...
[fn:50] The link is: https://orgmode.org

Org mode extends the number-based syntax to named footnotes and optional inline definition. Here are the valid references:

[fn:NAME]

A named footnote reference, where NAME is a unique label word, or, for simplicity of automatic creation, a number.

(note: This is the inline definition of this footnote)

An anonymous footnote where the definition is given directly at the reference point.

[fn:NAME: a definition]

An inline definition of a footnote, which also specifies a name for the note. Since Org allows multiple references to the same note, you can then use [fn:NAME] to create additional references.

Footnote labels can be created automatically, or you can create names yourself. This is handled by the variable org-footnote-auto-label and its corresponding STARTUP keywords. See the docstring of that variable for details.

The following command handles footnotes:

C-c C-x f

The footnote action command.

When point is on a footnote reference, jump to the definition. When it is at a definition, jump to the—first—reference.

Otherwise, create a new footnote. Depending on the variable ~org-footnote-define-inline~(note: The corresponding in-buffer setting is: #+STARTUP: fninline or #+STARTUP: nofninline.), the definition is placed right into the text as part of the reference, or separately into the location determined by the variable org-footnote-section.

When this command is called with a prefix argument, a menu of additional options is offered:

Depending on the variable ~org-footnote-auto-adjust~(note: The corresponding in-buffer options are #+STARTUP: fnadjust and #+STARTUP: nofnadjust.), renumbering and sorting footnotes can be automatic after each insertion or deletion.

C-c C-c

If point is on a footnote reference, jump to the definition. If it is at the definition, jump back to the reference. When called at a footnote location with a prefix argument, offer the same menu as C-c C-x f.

C-c C-o or mouse-1/2

Footnote labels are also links to the corresponding definition or reference, and you can use the usual commands to follow these links.

1. 37

   LaTeX is a macro system based on Donald E. Knuth's TeX system. Many of the features described here as "LaTeX" are really from TeX, but for simplicity I am blurring this distinction.

   Backrefs: 1

2. 38

   When MathJax is used, only the environments recognized by MathJax are processed. When dvipng, dvisvgm, or ImageMagick suite is used to create images, any LaTeX environment is handled.

   Backrefs: 1

3. 39

   These are respectively available at https://sourceforge.net/projects/dvipng/, http://dvisvgm.bplaced.net/ and from the ImageMagick suite. Choose the converter by setting the variable org-preview-latex-default-process accordingly.

   Backrefs: 1

4. 40

   This works automatically for the HTML backend (it requires version 1.34 of the htmlize.el package, which you need to install). Fontified code chunks in LaTeX can be achieved using either the listings LaTeX package, minted LaTeX package, or by using engrave-faces. Refer to org-latex-src-block-backend for details.

   Backrefs: 1

5. 41

   Source code in code blocks may also be evaluated either interactively or on export. See Working with Source Code for more information on evaluating code blocks.

   Backrefs: 1