Keyword #

Node.js, being a JavaScript runtime, inherits many keywords from the language itself. Understanding these keywords is essential for effective server-side development. Here’s a concise overview of some key Node.js keywords:

require: #

The require keyword is fundamental in Node.js for importing modules. It allows you to include functionality from other files or third-party packages into your application.

const fs = require('fs'); // Importing the 'fs' module for file system operations

module.exports: #

This keyword is used to expose functions, objects, or values from a module to make them accessible in other parts of your application.

// mathOperations.js
module.exports = {
    add: (a, b) => a + b,
    subtract: (a, b) => a - b
};

exports: #

Similar to module.exports, exports is used to make functions or variables available outside the module. It is often used when exporting multiple functions.

// mathOperations.js
exports.multiply = (a, b) => a * b;

require.resolve: #

This method is used to get the resolved filename of a module.

const filePath = require.resolve('./myModule.js');

__dirname and __filename: #

These variables provide the directory and filename of the current module, respectively. They are useful for constructing file paths.

console.log(__dirname);    // Current directory
console.log(__filename);   // Current filename

process: #

The process object provides information about the Node.js process and allows interaction with it. It includes events, methods, and properties for process management.

process.exit(); // Exit the Node.js process

console: #

The console object is crucial for debugging and logging information. It provides methods like log, error, and warn.

console.log('Hello, Node.js!');

global: #

The global object represents the global scope in Node.js. Variables declared without the var, let, or const keyword become properties of the global object.

global.myVariable = 'I am global!';

Buffer: #

In Node.js, the Buffer keyword is used to handle binary data directly. It is particularly useful when dealing with file streams and network operations.

const buffer = Buffer.from('Hello, Node.js!', 'utf-8');

exports vs. module.exports: #

Understanding the difference between exports and module.exports is crucial. While both are used for exposing functionalities, module.exports is a reference to the object that is actually returned as the result of a require call.

In summary, these keywords form the foundation of Node.js development. Whether managing modules, handling file system operations, or interacting with the process environment, a solid grasp of these keywords is essential for building robust and scalable server-side applications.