A blog site covering the basic concepts of NodeJS.

• NodeJS (https://nodejs.org/en/)

• Technologies:
  • NodeJS - Main Framework
• Tools:
  • VS Code - IDE
  • GitBash - Version Control
  • Chrome - Web Browser (others can also be used like Chrome, Safari, Firefox)

First, verify if your machine has the node installed by running the command node -v in a teminal. If you get to see a version, that means node is installed, otherwise, visit the official page of node to install the latest version of node js. After doing so, verify again following the same method.

Once the node is installed, you can use it in a terminal by using the command node and start to code in JS.

Alternatively, we can create a js file, and run it by using the command node <path/to/file>

JS has been confined to run in the browser for a long and used for FE and add interactivity. Node allows JS to run on the machine or server.

Computer understands machine language which is in bits. On top of that, a simpler language i.e. assembly language is used. Then we have programming langs like C++ which then compiles to assembly and so on.

JS is more higher level language so the computer doesnt understands it. It can run inside a browser. Inside browser, an engine called V8 runs, which is written in c++ by google which compiles JS to machine code in runtime. So the computer understands the JS inside the context of browser.

To run JS outside a browser, NodeJS comes into play. V8 engine also lives in node. NodeJS is also written in C++ that is why it can run on computer or a server. After installing node js, it can take JS, it runs it through the V8 engine/compiler and compiles the JS in machine language.

Apart from being a wrapper to V8 engine, node also hooks into V8 engine to add more funcionality to JS. Things like read/write a file on a computer, connection to a DB or act as a server for content.

Since we are using the JS outside the browser now, we lose access to JS features like DOM, we cant interact with HTML but we dont need it cuz we are using it as a BE server.

We'll use node to handle the requests from a browser or a client. The flow would be somewhat like: a request comes from the browser, Node accepts it and fetches data from DB/files and formulates a response. That response could be an HTML page with dynamic data embedded or with some CSS or image data etc.

• No need to learn extra language for BE
• Can share code for BE and FE
• Massive community
• Huge amount of 3rd party packages