The capabilities of node.js

The capabilities of node.js ()

Node.js is a platform for writing JavaScript applications outside web browsers. This is not the JavaScript we are familiar with in web browsers! For example, there is no DOM built into Node.js, nor any other browser capability.
The network layer of Node.js is low level while being simple to use. For example, the HTTP modules allow you to write an HTTP server (or client) using a few lines of code. This is powerful, but it puts you, the programmer, very close to the protocol requests and makes you implement precisely those HTTP headers that you should return in request responses.
Typical web application developers don't need to work at a low level of the HTTP or other protocols. Instead, we tend to be more productive, working with higher-level interfaces. For example, PHP coders assume that Apache (or other HTTP servers) is already there providing the HTTP protocol, and that they don't have to implement the HTTP server portion of the stack. By contrast, a Node.js programmer does implement an HTTP server to which their application code is attached.
To simplify the situation, the Node.js community has several web application frameworks, such as Express, providing the higher-level interfaces required by typical programmers. You can quickly configure an HTTP server with baked-in capabilities such as sessions, cookies, serving static files, and logging, letting developers focus on their business logic. Other frameworks provide OAuth 2 support, or focus on REST APIs, and so on.


Command-line tools (in shell script style)
An interactive-terminal style of program that is Read-Eval-Print Loop (REPL)
Excellent process control functions to oversee child processes
A buffer object to deal with binary data
TCP or UDP sockets with comprehensive event-driven callbacks
DNS lookup
An HTTP, HTTPS and HTTP/2 client/server layered on top of the TCP library filesystem access
Built-in rudimentary unit testing support through assertions
web application frameworks
Express


		web application frameworks	Express