What is Express?
The backend framework Express, released in 2010 and supported by Node.js, can be used to handle routing, generate ‘views’ for request responses, and define an application’s basic specifications. Express can be used with any database that Node supports, such as MongoDB, PostgreSQL, and Redis (though it’s not necessary to use a database with Express).
The following code creates a server without using Express. The server runs on port 3000, allowing a user to go to “localhost:3000/” and see the string “Hello World!”.
This illustrates that it’s not necessary to use Express to employ Node’s HTTP request response cycle. However, Express makes it easier to define routes and set up some basic specifications for an app. After installing Express, the following code should also render “Hello World!” at “localhost:3000/”:
Express’s website describes the framework as “fast, unopinionated, minimalist,” because its simply a layer on top on Node.js that allows developers use any file structure, pattern, or additional middleware they choose. This makes it easy to build simple applications without unnecessary bulk.