Update guide (#36)

writeup/Introduction.md

@@ -69,6 +69,13 @@ For context, JavaScript comes from a standard called [ECMAScript](https://en.wik
 
 However, MongoDB doesn't enforce data types like SQL databases do. So, we use a JavaScript library called [Mongoose](https://mongoosejs.com) to interface with MongoDB and provide extra type checks, helper functions, and more.
 
+<details>
+<summary><strong>ℹ️ Definition: Database</strong></summary>
+
+_A **database** is a specialized place for storing large amounts of data in the backend of an application. Examples of types of data we could store include usernames, passwords, profile pictures, post/comment text, order numbers, chat messages, payment information, and much more. We typically want to store these in the backend so that a user can log in on a different device and still have access to the same information._
+
+</details>
+
 </details>
 
 ### Node
@@ -154,6 +161,23 @@ Throughout this guide, we include pointers on Git usage to help you practice the
 
 </details>
 
+## Quick links
+
+Here are some links to documentation and guides that you may find helpful:
+
+- Mozilla Developer Network (MDN) references: Each is detailed and thorough, often with explanations of best practices too
+  - [JavaScript reference](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference)—syntax, operators, built-in objects and functions
+  - [HTML reference](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference)—elements and attributes
+  - [CSS reference](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference)—properties, pseudo-classes, selectors
+- [TypeScript language reference](https://www.typescriptlang.org/docs/handbook/utility-types.html)
+  - Also see the [Handbook](https://www.typescriptlang.org/docs/handbook/intro.html) for a higher-level overview of each concept
+- [Mongoose API reference](https://mongoosejs.com/docs/api/mongoose.html)
+- [Express API reference](https://expressjs.com/en/api.html)
+- [React reference](https://react.dev/reference/react)
+  - [Built-in hooks](https://react.dev/reference/react/hooks)
+  - [Built-in DOM components](https://react.dev/reference/react-dom/components)
+- [CSS-Tricks flexbox guide](https://css-tricks.com/snippets/css/a-guide-to-flexbox/)
+
 ## Before we begin
 
 This process is **not** an assessment of your skill level. There is no competition or evaluation based on your "performance." So, don't hesitate to use all of the resources available to you to better understand the concepts we discuss. Consult the Internet, your peers, the **#onboarding** Slack channel, your engineering manager, PVP members, or whoever/whatever else comes to mind! We want to facilitate the learning process for you, and we know it's subjective and unique to each individual. Do whatever it takes to maximize your own learning.

writeup/part-0/0-0-Install.md

@@ -15,11 +15,11 @@ Follow the steps below to install VS Code:
 1. Download VS Code for your operating system from the [VS Code downloads page](https://code.visualstudio.com/download).
 2. Follow the installer instructions.
 
-## Prettier extension
+## Prettier and ESLint extensions
 
-No matter what editor you choose, we **strongly** recommend that you also install the corresponding Prettier extension (and your engineering manager may require you to do so). We use Prettier to automatically format JavaScript/TypeScript code (such as fixing indentation) so it's more consistent and easier to read.
+No matter what editor you choose, we **strongly** recommend that you also install the corresponding Prettier and ESLint extensions (and your engineering manager may require you to do so). We use Prettier to automatically format JavaScript/TypeScript code (such as fixing indentation) so it's more consistent and easier to read, and we use ESLint to make sure the code follows certain rules so it's more likely to work correctly.
 
-Follow the steps below to install and configure the Prettier extension for VS Code:
+Follow the steps below to install and configure the [Prettier extension for VS Code](https://marketplace.visualstudio.com/items?itemName=esbenp.prettier-vscode):
 
 1. Navigate to the Extensions tab in the left sidebar.
 2. Enter "Prettier" in the search bar and select the extension published by prettier.io.
@@ -32,6 +32,8 @@ Follow the steps below to install and configure the Prettier extension for VS Co
 6. Finally, find the "Editor: Format On Save" option and make sure it's checked.
    <img src="../images/configure-vs-code.png">
 
+Similarly, install the [ESLint extension](https://marketplace.visualstudio.com/items?itemName=dbaeumer.vscode-eslint) published by Microsoft as well. This extension doesn't require any additional configuration.
+
 ## Git
 
 1. Check your Git version by entering `git --version` in your command prompt.