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Learning Web Design Third Edition- P5

Learning Web Design Third Edition- P5:Everything you need to know to create professional web sites is right here. Learning Web Design starts from the beginning defining how the Web and web pages work and builds from there. By the end of the book, you'll have the skills to create multi-column CSS layouts with optimized graphic files, and you'll know how to get your pages up on the Web. | Putting It All Together When I first began writing HTML it helped me to think of the tags and text as beads on a string that the browser deals with one by one in sequence. For example when the browser encounters an open bracket it assumes all of the following characters are part of the markup until it finds the closing bracket . Similarly it assumes all of the content following an opening h1 tag is a heading until it encounters the closing h1 tag. This is the manner in which the browser parses the HTML document. Understanding the browser s method can be helpful when troubleshooting a misbehaving HTML document. But where are the pictures Obviously there are no pictures in the HTML file itself so how do they get there when you view the final page You can see in Figure 2-3 that each image is a separate graphic file. The graphics are placed in the flow of the text with the HTML image element img that tells the browser where to find the graphic its URL . When the browser sees the img element it makes another request to the server for the image file and then places it in the content flow. The browser software brings the separate pieces together into the final page. The assembly of the page generally happens in an instant so it appears as though the whole page loads all at once. Over slow connections or on slower computers or if the page includes huge graphics the assembly process may be more apparent as images lag behind the text. The page may even need to be redrawn as new images arrive although you can construct your pages in a way to prevent that from happening . Putting It All Together To wrap up our introduction to how the Web works let s trace the stream of events that occur with every web page that appears on your screen Figure 2-4 . O You request a web page by either typing its URL for example http jen-skitchensite.com directly in the browser or by clicking on a link on the page. The URL contains all the information needed to target a specific document on a .