wip(shared): Started working on jargon overhaul

See #6017

markdown/dev/guides/markdown/jargon/en.md

@@ -4,7 +4,7 @@ order: yyy
 ---
 
 Jargon are terms that could throw off new users.
-Rather than create a glossary on every page, we use a plugin to manage
+Rather than create a glossary on every page, we use MDX to manage
 jargon terms for us. This page shows you how to use it.
 
 <Tip compact>Think of jargon as glossary terms</Tip>
@@ -23,13 +23,13 @@ We are migrating from _cjs_ to _esm_ modules
 
 ## Adding jargon
 
-To add a new jargon term, you need to add it to the jargon file for the
-website you'd like to add it to:
+To add a new jargon term, you first need to document it, than you can add it to
+the jargon component for the website you'd like to add it to:
 
 | Website | Jargon file | GitHub link |
 | ------- | ----------- | ----------- |
-| freesewing.dev | `sites/dev/jargon.mjs` | [jargon.mjs](https://github.com/freesewing/freesewing/blob/develop/sites/dev/jargon.mjs) |
-| freesewing.org | `sites/org/jargon.mjs` | [jargon.mjs](https://github.com/freesewing/freesewing/blob/develop/sites/org/jargon.mjs) |
+| freesewing.dev | `sites/dev/components/jargon.mjs` | [jargon.mjs](https://github.com/freesewing/freesewing/blob/develop/sites/dev/comonents/jargon.mjs) |
+| freesewing.org | `sites/org/components/jargon.mjs` | [jargon.mjs](https://github.com/freesewing/freesewing/blob/develop/sites/org/components/jargon.mjs) |
 
 The file consists of key/value pairs where:
 

markdown/dev/reference/terms/cjs/en.md

@@ -0,0 +1,18 @@
+---
+title: cjs
+---
+
+**cjs** stands for **CommonJS**. It is a module system for JavaScript that was
+popularized by NodeJS, and as such typically used in server-side JavaScript.
+
+CommonJS uses the **require** keyword to import modules:
+
+```js
+const fs = require('fs')
+```
+
+In recent years, **cjs** is increasingly being replaced by **esm**, or ECMA
+Script Modules which is the official module system of the JavaScript language,
+and the future-proof choice.
+
+Since version 3, FreeSewing is ESM-only.

markdown/dev/reference/terms/en.md

@@ -0,0 +1,7 @@
+---
+title: Terminology
+---
+
+These are terms that we use on this website that may or may not be new to you:
+
+<ReadMore />

markdown/dev/reference/terms/esm/en.md

@@ -0,0 +1,17 @@
+---
+title: esm
+---
+
+**esm** stands for **ECMAScript Modules** and is the official module system of
+the JavaScript language, supported both in the browser, and on the server.
+
+While ESM is the official standard, before it existed people would typically use CJS outside the browser, as it was popularized by NodeJS.
+Some libraries still are not available in ESM, but FreeSewing has been ESM-only since version 3.
+
+
+ESM uses the **import** keyword to import modules:
+
+```js
+import fs from 'fs'
+```
+

markdown/dev/reference/terms/variadic/en.md

@@ -0,0 +1,14 @@
+---
+title: Variadic
+---
+
+A **variadic** function is a function that accepts a variable number of arguments.
+
+For example, JavaScript's `console.log` method is variadic:
+
+```js
+console.log('one')
+console.log('one', 'two')
+console.log('one', 'two', 'three')
+console.log('It', 'word', 'regardless', 'of', 'how', 'many', 'arguments', 'you', 'pass')
+```