Pick any that you like from https://emacsrocks.com. My favourite is https://emacsrocks.com/e13.html well worth watching until the end where it all comes together.

You might be interested in this talk at next weekend’s Emacs Conf:

How to show not tell people about the wonders of Emacs

any IDE is just as extensible by using Plug Ins

Lisp. Up, down, around, inside, across, between, under, at, through, into.

It’s the always-on REPL that’s the kicker.

(defun invert-case ()
  (backward-delete-char-untabify 1)
  (insert (funcall (if (< last-command-event ?a)
		       #'downcase
		     #'upcase)
		   last-command-event)))

(add-hook 'post-self-insert-hook #'invert-case)

Then C-u C-M-x on invert-case to convey the larger point that emacs is always running within a gdb-like harness. Your buddy will immediately bristle at the prohibitive investment necessary to achieve this pointless and trivial hack, at which point he’ll have truly grokked emacs.

First I wouldn’t concern myself too much with trying to explain what differentiates Emacs from an IDE. Life is too short to get into such debates. I can’t really summarize why anyone should care about Emacs vs their IDE of choice.

For me what separates Emacs from vscode for instance is not the IDE aspects but the integration with the broader ecosystem. I’m a PM that works with technical and data heavy products. The details matter. I frequently walk through the pipelines and code of my product to understand how it is implemented by the team(s).

For example you can break my underlying product down into 3-4 large blocks of pipelines. Each pieline has 6-7 stages that mix Spark and other Python jobs. For each pipeline and stage I have my own little literate org file that points to code, has small samples of inputs and outputs, and generally speaking allows a non data engineering professional such as myself keep up with people that are far better and keeping this all in their head.

I write down questions as I do this to browse and/or raise with the team. I can, when questioned by our senior leadership, truly explain what it is our team did and the impact it had.

I can’t do that with an IDE. I can’t see an easy way to do that with any of the other note taking tools. I can’t jump between code browsing, executing and writing as seamlessly anywhere else.

The lisp environment of Emacs makes it unique. Also it’s support for dynamic modules gives you a TON of extra power for certain cases where lisp is not appropriate; integrating 3rd party software like web browsers in a performant way.

If your goal is to simply use the editor then the lisp environment doesn’t give you an advantage. But if you want to treat the editor as a tool you mold like clay to your tiniest yak shaving need then it gives you a LOT.

For comparison, let’s look at Netbeans. A stereotypical traditional IDE. . If you try to write a plugin Netbeans you are first met with boilerplate. Menus, a bunch of strange plugin related code generated. You have to learn the plugin boilerplate system to get started. Now you wrote a little code and are ready to test/observe it’s behavior! how do you do that? you build/run and spawn YET-ANOTHER-NETBEANS which may take a few minutes. The write/observe feedback loop is painfully slow. (FYI I love and use Netbeans. I’m dunking on it but it has some advantages even over modern IDEs like Jetbrains).

Now let’s look at Emacs. We start by writing a function. Then immediately observing/testing their behavior. There is no boiler plate. We are not cordoned off to a special “plugins” area. We just straight to the good stuff, the functionality. Instead of waiting 5 minutes to build/observe what we wrote, it happens IMMEDIATELY as we write it using lisp’s EVAL-loop. It affects our running Emacs instance, no need to spawn another.

I lied a little bit. Emacs packages DO have boiler plate that you should conform to before publishing. But it’s not required, and not where you start. For your personal stuff, it may simply be a collection of functions. Then bind appropriate functions to keys.

An anecdote. Just yesterday I was writing some Go (lang) code and running the linter. Most of the time I like to run the linter at the project root folder. But at that moment I only care about the package I’m working on in the current folder or maybe 1 level up. I whipped up a little helper function where I can select 1 of 3 options: current folder, project-root folder, Custom folder. The project root folder is detected by heuristics using Emacs project library. If I choose Custom, then i input a folder via completing read. This little fn scratches MY itch. A tiny little inconvenience solved in 5 minutes. If i tried to solve that in Netbeans… it would take 5 minutes just to build it and spawn another Netbeans instance.

One of the junior coders was using vscode but with vi keybindings. He heard one of the seniors talk about their love of vi and he thought he had to learn it as well. I told him that, learning vi is handy because it is often one of the only editors you find on a freshly installed GNU/Linux system, but in the end VSCode is very capable without learning silly shortcuts. I know that, if I had to pick an IDE now I would definitely choose VSCode. I have spent so much time configuring my EMacs that it would be a waste of time to start it again.

You might get pretty far just by explaining that all emacs “plugins” use the same language as the editor, and then explaining the C-h family of keybinds that let you see documentation for every variable and function.

Then open one of those help pages for a package to show it and highlight the part where it tells you what file the function comes from, even for 3rd party packages. Then highlight how you can extend emacs in the same way, just writing some elisp on a file instead of needing to create an entire plugin.

A lot of emacs really needs to be discovered, but I’d imagine most developers could appreciate good documentation, the ability to see exactly what code is doing, and the option to override or extend that functionality very easily.

Not the best person to answer - glanced the replies, and seeing people who seem very articulate so definitely read their points of view.

My personal thought is being a “literate programmer” - I should be able to understand what my tools are doing and how it affects things. If I spend to much time with plugins - I sort of miss exactly what they do. With emacs - I have the code and I have a community.

Probably the most simple examples for me are

1. Showing the multitude of packages for something like an email client, Margit, etc and how you can mix them together with org linking, using babel, etc. showing the deep level of integration you get

2. Simply show functionality in the editor and how you would like it to change. Rather that writing a whole package to do it. Use the help to go to the source and redefine that function in your config. Doesn’t require them to know elisp to understand but it gets the point across that everything is at your fingertips.

Show him one of the email clients on GNU Emacs. Vterm’s directory tracking is also unique.

Emacs is a programmable interface to a computer. While it is frequently used to program itself to program other things, it is a foundational bootstrap tool.

IDE’s seek to present a set of features that fills that domain of work. You hit a ceiling in that world. With Emacs, you continue molding it to things you get value out of years and decades later, after that IDE went away when its most popular language or framework went into decline.

In the upcoming landscape of AI’s with more well-defined type interfaces and symbolic representations, tools like Emacs will be at the forefront of composing these tools into the long tail of cottage industries of what will amount to a revolution in IP, programming, and human-computer interfaces.

I don’t. I dont care what other people use. Folks noticing I have language server support in a terminal editor is funny though.

It is not so much about other tools or languages not being extensible; most quality ones are extensible. It is about how easy is to extend it since the text editor, debugging tools, and some other useful stuff like shell integration (process control, I/O), networking for example, are built into the extension language.

It is very easy to write a small tool that automates something, like a say project creation for Emacs compared to for example Eclipse, Netbeans, or VisualStudio. Since Emacs GUI is in essence a glorified console, it is relatively easy to integrate CLI, text-based tools with Emacs.

I mean, as a practical matter they are correct - most things people care about IDEs doing are just built in in other IDEs or doable via plugins. emacs is extremely niche and most people are correct to use something else.

It is an important skill to not care what other people use and not care what they think about what you use.