Org Mode

#+MACRO: img (eval (format "[[file:%s.%s]]" $1 (if (org-export-derived-backend-p org-export-current-backend 'latex) "pdf" "svg")))

Add this line in the org file to create a macro. Then use it as follows (don't add the extension at the end):

{{{img(path/to/image)}}}

When using source blocks that don't have a babel backend add the parameter :exports code to prevent org-mode from complaining about the backend being not found. Because even though the :eval no-export is present, org babel still tries to parse the params and do some stuff with the source block.

So instead of

#+begin_src json
  {
    "name" : "Bibek Panthi",
    "species" : "Homo sapiens"
  }
#+end_src

do

#+begin_src json :exports code
  {
    "name" : "Bibek Panthi",
    "species" : "Homo sapiens"
  }
#+end_src

https://howardism.org/Technical/Emacs/literate-devops.html

You can run org babel sh source blocks on remote systems using :dir parameter.

Consider the following:

#+begin_src sh :dir /etc :results raw :wrap verbatim
head passwd
#+end_src

This is same as:

#+begin_src sh :results raw :wrap verbatim
head /etc/passwd
#+end_src

The :dir parameter accepts anything that emacs accepts for opening files, including paths opened by tramp. For example, if you have a server server.com and you open some file by M-x find-file /ssh:server.com:/home/bpanthi977/test.org. Then in similar way, you can specify :dir parameter to work on a remote directory:

#+begin_src sh :dir /ssh:server.com:/etc :wrap verbatim :results raw
head passwd
#+end_src

#+RESULTS:
#+begin_verbatim
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
#+end_verbatim

Add the following to the top of org file:

#+begin_export latex
\\AtBeginSection[]{
  \\begin{frame}
  \\vfill
  \\centering
  \\begin{beamercolorbox}[sep=8pt,center,shadow=true,rounded=true]{title}
    \\usebeamerfont{title}\\insertsectionhead\\par%
  \\end{beamercolorbox}
  \\vfill
  \\end{frame}
}
#+end_export

#+begin_export latex
\let\oldsection\section
\renewcommand\section{\clearpage\oldsection}

\clearpage
#+end_export

#+BEGIN_EXPORT latex
\let\oldsection\section
\renewcommand\section{\clearpage\oldsection*}

\clearpage
#+END_EXPORT

#+begin_export latex
\usepackage{listings}
\usepackage{color}
\definecolor{codegreen}{rgb}{0,0.6,0}
\definecolor{codegray}{rgb}{0.5,0.5,0.5}
\definecolor{codepurple}{rgb}{0.58,0,0.82}
\definecolor{backcolour}{rgb}{0.95,0.95,0.92}


\lstdefinestyle{mystyle}{
    backgroundcolor=\color{backcolour},
    commentstyle=\color{codegreen},
    keywordstyle=\color{magenta},
    numberstyle=\tiny\color{codegray},
    stringstyle=\color{codepurple},
    basicstyle=\ttfamily\footnotesize,
    breakatwhitespace=false,
    breaklines=true,
    captionpos=b,
    keepspaces=true,
    numbers=left,
    numbersep=5pt,
    showspaces=false,
    showstringspaces=false,
    showtabs=false,
    tabsize=2,
    upquote=true
}

\lstset{style=mystyle}
#+end_export

https://cachestocaches.com/2016/9/my-workflow-org-agenda/

For this you can wrap the image link/attachment inside a drawer. And then configure emacs to not export that drawer.

For example:

#+OPTIONS: d:(not "noexport" "logbook")

:noexport:
attachment:image.png
:end:

It can be configured globally by setting the value of org-export-with-drawers. It is a list of drawers to be exported or if the list starts with not, it the list of drawers to not export.

(setq org-export-with-drawers '(not "noexport" "logbook"))

The default value of org-export-with-drawers is (not "LOGBOOK") that's why in above examples we keep that value too and also specify noexport drawers to be not exported.

Alternatively, you can specify d:nil to prevent explorting any drawers.