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[SOUND] >> Hi there.

My name is Chris and I'm a Java teacher here at Treehouse.

Chances are that you've spent some time online.

In fact, I know you've spent some time online,

since you're here taking this course now.

Even more, I know that you probably spend quite a bit of time on the internet,

given that you're learning path and

java, has probably taught you a few things before landing in this course.

You've probably poked around on many websites, whether that is the Treehouse

library, our forum, stack overflow, or the oracle java docs.

Or maybe it's during breaks from your learning that you spend the most

time online.

Twitter, Facebook, Instagram, Reddit, Buzzfeed.

While you're learning how to use Java to create programs to do sophisticated

things, do you ever look at the very sites you're browsing and

think, could I use Java to make a web application?

Fortunately for you, the answer is yes.

There are numerous ways to do this, and it's changed a lot throughout the years.

In this course,

we'll focus on using the Spring framework to help us accomplish this task.

We'll dive more deeply into the details of Spring, but

let me give you an overview here.

Writing a web application is like being the author of an ongoing dialogue.

As with any dialogue you might wonder who are the speakers?

For a basic web app, essentially there are two.

The server, and the client.

In general the user of a web application communicates with the server

through a web browser.

This could be Chrome, Safari, Firefox, Microsoft Edge, or maybe a mobile browser.

The web browser formats all user actions and sends them,

in a nicely formatted request, to the web server.

Upon receiving this request, the web server, according to how it's programmed,

crafts a nicely formatted response to send back to the browser.

The format of the request and

the response follows a very specific set of rules as defined by HTTP.

Or, the HyperText Transfer Protocol.

It is in the crafting of the response from a web server

where your Java code would come into play.

If you're a Java developer working on a web application,

likely most of your development time is spent here, on the web server.

You'd be writing the Java code necessary to respond to the requests coming from

your users' web browsers.

Coding a Java web app, means coding a bunch of components.

By component I simply mean a class or

collection of classes that handles a specific task in the application.

In a web application, your Java code needs a component to intercept the incoming

request, components to handle the requests to certain locations, and

more components to fetch and store any data related to the requester response.

And even more components to generate the response back to the web browser.

Now that's quite a few components.

Luckily, there are many libraries or frameworks that help you organize and

manage this request and response cycle.

One of the most popular for Java is the spring framework.

In this course we'll use the web components of the Spring framework

to write a site that serves as an animated GIF library.

We'll call this library GifLib.

This will be a website that lists a bunch of animated GIFs each with a name,

user and date uploaded.

Because the Spring framework provides some really sophisticated options for

writing web applications,

we'll take our time in fully understanding the setup of even a simple web app.

This will give you a solid foundation from which you can climb to more powerful,

industry ready apps.

So, when you're ready to start, head to the next video where we'll begin

installing what you'll need on your computer to code your first spring app.