In order to deliver the front-end of a website or web application to a user, a lot needs to happen behind the scenes on the back-end! Understanding what makes up the back-end can be overwhelming because the back-end has a lot of different parts, and different websites or web applications can have dramatically different back-ends. We covered a lot in this lesson, so let’s review what we learned:

• The front-end of a website or application consists of the HTML, CSS, JavaScript, and static assets sent to a client, like a web browser.
• A web server is a process running on a computer somewhere that listens for incoming requests for information over the internet and sends back responses.
• Storing, accessing, and manipulating data is a large part of a web application’s back-end
• Data is stored in databases which can be relational databases or NoSQL databases.
• The server-side of a web application, sometimes called the application server, handles important tasks such as authorization and authentication.
• The back-end of web application often has a web API which is a way of interacting with an application’s data through HTTP requests and responses.
• Together the technologies used to build the front-end and back-end of a web application are known as the stack, and many different languages and frameworks can be used to build a robust back-end.

Now that you have a sense for server-side web development and what the back-end is, you’re ready to dive in and learn about the different parts in more depth!