When a team of builders begin constructing a building, one of their key tasks is to assemble the frame. It doesn't matter what building it is. It always starts with a frame of beams and rafters. Once in place, the frame guides the rest of the construction. If you compare a building with a web page, an HTML document is a lot like the frame, is a basic structure assembled with different components such as tags and elements. In this video, you will learn about HTML documents and the difference between HTML tags and elements. To begin, let me tell you a short story about where it all started. Sir Tim Berners-Lee, a physicist, often thought about how he and his colleagues from around the world would share information. He was so used to browsing information online that it might seem a silly thing to ponder about. Actually, that question was very relevant at the time and started the development of HTML, which you'd like to explore the very first web page. I know just where to find it. The first web page was created in 1999 by Sir Tim Berners-Lee. He worked at the European Organization for Nuclear Research or CERN, and originally proposed HTML. The first version of HTML was released in 1991 along with the first web browser and web server. HTML stands for Hypertext Markup Language. But what does that mean exactly? Hypertext is text which contains links to other text. Markup refers to tags and elements used within a document. For now, let's just focus on some of the basics of HTML. HTML is simply a text file with a specific structure that consists of elements and tags. Also take note that HTML files usually have a dot HTML suffix. For instance, when you visit a website, the first page that is returned to the browser is often called index.html. Now, let's explore what HTML tags and elements are. Each HTML element consists of an opening tag enclosed in angle brackets. For example to create a paragraph, you type a left angle bracket, the letter p for paragraph, and then a right angle bracket. Most elements are paired with a closing tag, which has a forward slash off to the left angle bracket. For example you close the paragraph element with a left angle bracket, a forward slash the letter p and a right angle bracket. HTML elements usually have some content inside them. For example between the opening and closing tags of a paragraph, you add the text of the paragraph you want to write. HTML elements can also contain other elements, for example you can add an italics element inside a paragraph element to make texts appear in italics. Elements can also be empty or self-closing, meaning they do not have a closing HTML tag. One example of a self-closing element is the line break tag. You can add a line break tag in a paragraph tag to move content to the following line by typing left angle bracket, the letters br, then right angle bracket. At the end of a self-closing tag, you simply add a right angle bracket. You can also close the right angle bracket by typing a forward slash right before it. Now that you know what elements and tags are, you will explore what HTML standards are. The rules and structure for elements and tags are known as the HTML specification. The HTML specification is maintained by the World Wide Web Consortium, or W3C, as it is commonly known. Whenever the HTML specification changes, a new version of HTML is standardized, the current version is HTML 5. To summarize, HTML elements with their opening and closing tags, and angle brackets build up an HTML document. These elements form the structure of a web page and describe to the web browser what to display. For example the browser reads an HTML page that has an image tags display an image file called icon.png. Next, it reads a p tag to display a paragraph under that image. But the browser reads the HTML document and displays the web page to the user in a very basic format. Now, if you want to tell the browser how to display the web page, you should use CSS. You will learn more about CSS in this course. By now, you have learned how HTML tags are used to create elements that build the structure of a web page. You'll have an opportunity to explore HTML in action in this course.