Web applications consist of two parts. There's a front end and a backend, and they serve two completely different purposes, but without a front end or a backend, you have an application that's, well, it's not really an application. Front end is basically what runs inside of the browser. So that means HTML, CSS, and JavaScript. HTML allows us to define the structure of what is rendered inside of the browser.

HTML allows us to define the structure of what is rendered inside of the browser. CSS is cascading style sheets and it allows us to style our HTML and give our application a certain look and feel. But then we have JavaScript. JavaScript primarily allows us to interact with the front end. JavaScript allows us to create a dynamic experience. So for a web application,

JavaScript allows us to create a dynamic experience. So for a web application, the front end is basically anything running inside of the browser. It is what the user interacts with, but then there's the backend. The backend for an application is a server, is a specialized computer that is going to process and work with the information coming from the user. So the first thing that the server needs is a language or,

and work with the information coming from the User. So the first thing that the server needs is a language or, or some kind of framework, php, Ruby, C Sharp, there's even JavaScript can run on the server. But as I mentioned, the whole reason why we use applications is to work with and manipulate data. Whatever language or framework that we use is going to interact with some kind of data store. It's usually a database because databases give us a very structured way.

It's usually a database because databases give us a very structured way of storing data. So therefore our framework is going to process that data by interacting with that database so that it can do whatever work that we wanted it to do. And then finally, whenever the back end is done doing whatever it needs to do, it sends its response back to the front end. So the overall flow looks like this.

to the front end. So the overall flow looks like this. A User requests something from the front end. The request travels to the backend where the backend will fetch the information from the database process, that data, however it needs to process it, and then it sends back the response to the front end so that it can be displayed in the browser. The front end and the backend have to work in harmony together.

The front end and the back end have to work in harmony together. They create a complete and functional application.