General HTML5/CSS3
Express JS is the E in the MEAN software stack. It runs along with MongoDB database, AngularJS front-end framework and Node JS environment. Every software stack needs an operating system, a database, a server and a development platform. Express JS is developed by T J Holowaychuk, StrongLoop and others and is written in JavaScript. It is a free and open-source software under MIT licence. It is a web application framework which provides a robust set of features for web and mobile applications.
The Express JS and Node JS gave a new backend functionality to JavaScript. For the first time it allowed developers to build softwares with JavaScript on the server side. Together both Node JS and Express JS made it possible to build an entire website with JavaScript. Now people can develop a server-side applications with Node JS and publish that application as website with Express. Since Node JS was not capable to build websites alone, so Express JS came with some built-in structure and functions that are required to build a website. It is a lightweight framework which provides developers with extra built-in web application features and Express API (Application Programming Interface) without overriding the already present features of Node JS. and due to this we can say that the Node JS with Express JS have changed the way developers build their websites.
Why use Express JS?
There are some of the important features or advantages of Express JS which tells us why we should use Express JS:-
1- It helps to make Node JS web application development fast and easy.
2- It makes it easy to configure and customize.
3- It allows us to define routes of your application based on HTTP methods and URLs.
4- It includes various middleware modules that help us to perform additional tasks on request and response.
5- It is also easy to integrate with different template engines like Jade, Vash, EJS,etc.
6- It allows to define error handling middleware.
7- It makes it easy to serve static files and resources for web application.
8- It also allows to create REST API server.
9- It is easy to connect to database such as MongoDB, Redis, MySQL.