Add content in Node.js roadmap (#2170)

* Update 100-builtin-modules.md

add content on "built-in modules" node in Node.js roadmap

* Update readme.md

add content on "common built-in modules" node in the Node.js roadmap

* Update readme.md

* Update content/roadmaps/107-nodejs/content/117-nodejs-common-modules/100-builtin-modules.md

Co-authored-by: Kamran Ahmed <kamranahmed.se@gmail.com>

content/roadmaps/107-nodejs/content/117-nodejs-common-modules/100-builtin-modules.md

@@ -1 +1,22 @@
-# Builtin modules
+# Builtin modules
+
+Built-in modules are already installed with `Node.js`, so you don't need to install them with any package manager (yarn, npm, etc.).
+
+- **fs**: dealing with the system files.
+- **os**: provides information about the operation system.
+- **net**: to build clients and servers.
+- **path**: to handle file paths.
+- **url**: help in parsing URL strings.
+- **events**: provides a method for interacting with events.
+- **http**: making Node.js transfer data over HTTP.
+- **console**: to log information in the console.
+- **assert**: provides a set of assertion tests.
+- **process**: provides information about, and control over, the current process.
+- **cluster**: able to creating child processes that runs simultaneously and share the same server port.
+- **perf_hooks**: provides APIs for performance measurement
+- **crypto**: to handle OpenSSL cryptographic functions.
+- **Buffer**: provides APIs to handling streams of binary data.
+
+<ResourceGroupTitle>Free Content</ResourceGroupTitle>
+<BadgeLink colorScheme='blue' badgeText='Official Website' href='https://nodejs.org/api/modules.html'>API documentation of Built-in modules</BadgeLink>
+<BadgeLink colorScheme='yellow' badgeText='Read' href='https://www.w3schools.com/nodejs/ref_modules.asp'>Built-in modules - w3schools</BadgeLink>

content/roadmaps/107-nodejs/content/117-nodejs-common-modules/readme.md

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-# Nodejs common modules
+# Nodejs common modules
+
+These are the common modules that come with `Node.js` out of the box. This module provides tools or APIs for performing out certain standard `Node.js` operations. like interacting with the file system, url parsing, or logging information to the console.