1. HTML Documents The declaration is not an HTML tag. It is an "information" to the browser about what document type to expect. In HTML5, the <!DOCTYPE> declaration is very simple. We write as <!DOCTYPE html> . The HTML document itself begins with <html> and ends with </html> . The visible part of the HTML document is between <body> and </body> . 2. HTML Language <html lang="en"> attribute is used for declare the language of the Web pages 3. This is the complete structure of HTML <!DOCTYPE html> <html lang="en"> <! --- for language ---> <head> <! --- we can write scripts here ---> <title>Page Title</title> </head> <body> <! --- we can write all the codes here ---> <h1>My First Heading</h1> <p>My first paragraph.</p> </body> </html>