HTML and CSS are a fundamental part of all websites. 0:00 But for many websites like Amazon, Facebook, and Twitter, HTML and CSS 0:04 are just two of many other technologies they use to provide their services. 0:08 You may have heard of JavaScript, PHP, Java, Python, MySQL or Ruby on Rails. 0:13 These are just a few of the technologies that are used to create today's 0:19 complex websites. 0:22 Web Development is often split into two areas, front end development and 0:24 back end development. 0:28 Front end developers use HTML, CSS and JavaScript to build what the client sees. 0:30 The stuff that runs on the browser. 0:34 Backend developers are responsible for what runs on the server. 0:38 They use languages like Python, Ruby, and 0:42 Java to work with databases to save, change, and retrieve data. 0:44 As an example, JavaScript runs in the browser to add interactivity to a page. 0:49 Like if you wanted to have a window pop up each time your user clicks a button or 0:54 if you wanted to display a group of images with the slide show. 0:58 You'd use HTML and CSS to build and style the slide show and JavaScript 1:01 to program the slide show images, so that they slide in and out of view. 1:07 Or think about a log in page for 1:11 website like Facebook, you'd use HTML to create input field and submit button. 1:12 And use CSS to control what the button and the input fields look like. 1:18 But when a user presses enter or click submit, you might use JavaScript 1:22 to make sure the information they submitted is formatted correctly. 1:26 That their email address contains an @ symbol, for example. 1:29 You also might use JavaScript to throw up an error or 1:33 a success message when the form is submitted. 1:35 And then you might need a backend language like PHP, Python, or 1:38 Ruby to save the username or email address to a database to retrieve it later. 1:41 That's how HTML and CSS fit into the larger field of web development. 1:47 As we've seen, HTML and CSS are the foundation of websites and 1:52 web applications. 1:56 If it's on the web, it uses HTML and CSS in some capacity, which is why 1:57 learning the basics is an excellent way to start your journey learning how to code. 2:02 In the next part of this course, 2:07 we're going to go into a little more detail about how web pages are structured 2:08 and learn all about the most common and useful HTML tags. 2:12 I'll see you there. 2:15