Starting with Express JS
Published: 2021-07-27 14:31:02

Express.js, or simply Express, is a back-end web application framework for Node.js, released as free and open-source software under the MIT License. It is designed for building web applications and APIs. It has been called the de facto standard server framework for Node.js. Express.js is a framework of Node.js which means that most of the code is already written for programmers to work with. You can build a single page, multi-page, or hybrid web applications using Express.js. Express.js is lightweight and helps to organize web applications on the server-side into a more organized MVC architecture.

It is important to learn javascript and HTML to be able to use Express.js. Express.js makes it easier to manage web applications. It is a part of a javascript-based technology called MEAN software stack which stands for MongoDB, ExpressJS, AngularJS, and Node.js. Express.js is the backend part of MEAN and manages routing, sessions, HTTP requests, error handling, etc.

The JavaScript library of Express.js helps programmers to build efficient and fast web apps. Express.js enhances the functionality of node.js. In fact, if you don’t use Express.js, then you have to do a lot of complex programming to build an efficient API. It has made programming in node.js effortless and has given many additional features.

## Why should you use Express JS
Express.js supports JavaScript which is a widely used language that is very easy to learn and is also supported everywhere. Therefore, if you already know JavaScript, then it will be really easy for you to do programming using Express.js.

With the help of Express.js, you can easily build different kinds of web applications in a short period of time. Express.js provides a simple routing for requests made by clients. It also provides a middleware that is responsible for making decisions to give the correct responses for the requests made by the client

Without Express.js, you have to write your own code to build a routing component which is a time consuming and tedious task. Express.js offers simplicity, flexibility, efficiency, minimalism, and scalability to the programmers. It also has the advantage of powerful performance as it is a framework of Node.js.

Node.js carries all the executions really fast with the help of Event Loop that avoids any kind of inefficiency. The powerful performance of Node.js and the ease of coding using Express.js are the most popular features loved by web application developers. Since Express.js is written in Javascript, you can build websites, web applications, or even mobile apps using it.

## Need of Express JS
The most valuable asset in any business is time. On top of that many programmers have the pressure to build efficient web apps in a short period of time. But coding web apps and testing them requires time. This is where Express.js becomes a lifesaver for programmers.

Express.js can reduce the coding time by half and still help us build efficient web applications. It not only reduces the time but it also reduces the effort required to build web apps with the help of its different features.

Another reason to use Express.js is JavaScript. Express.js allows even beginners to enter the field of web application development because it supports JavaScript. Javascript is very easy to learn for anyone even if they do not have any prior knowledge of any other languages. Therefore, Express.js allows young talent to enter the field of web app development and achieve success.

Node.js is event-driven and thus has the ability to handle thousands of client requests at the same time which is not possible with PHP.

In today’s world, real-time web apps and services are increasing in popularity. Node.js is designed exclusively to support real web applications. The most common example of a real-time web app would be live-chat. It involves thousands of users and real-time interaction that can be supported easily by Node.js.

Another asset of any business is money. It is important to use money efficiently to maximize profits. Since Express.js is an open-source and free web application that provides many great features, there is no reason left to not use it.

##Features of Express.js
### 1. Faster Server side development
Express.js provides many commonly used features of Node.js in the form of functions that can be readily used anywhere in the program. This removes the need to code for several hours and thus saves time.

### 2. Middleware
Middleware is a part of the program that has access to the database, client requests, and the other middlewares. It is mainly responsible for the systematic organization of different functions of Express.js.

### 3. Routing
ExpressJS provides a highly advanced routing mechanism that helps to preserve the state of the webpage with the help of their URLs.

### 4. Templating
ExpressJS provides templating engines that allow the developers to build dynamic content on the web pages by building HTML templates on the server-side.

### 5. Debugging
Debugging is crucial for the successful development of web applications. ExpressJS makes debugging easier by providing a debugging mechanism that has the ability to pinpoint the exact part of the web application which has bugs.

## Writing first Express JS program

```
const express = require("express");
      const app = express();
const port = 3100;
app.listen(port , ()=>{console.log("server is up and running")});
app.get('/', (req,res)=>{

res.send("Hello world")})
```
## Using Nodemon for Express JS
nodemon is a tool that helps develop node.js based applications by automatically restarting the node application when file changes in the directory are detected.

nodemon does not require any additional changes to your code or method of development. nodemon is a replacement wrapper for node. To use nodemon, replace the word node on the command line when executing your script.

### installation
for your Node package Manager(npm)

npm i nodemon

you can save nodemon as dev dependency

npm install --save-dev nodemon

## Conclusion
I wrote this blog for absolute beginners who are starting their express journey as backend developers and this blog will help to set up the work environment and starting their server. hope this blog will be helpful. do share your feedback and share.