Your Magic Carpet - The Browser
When you first get a computer one of the first things that you do is open your Internet browser and begin to look around the web. You click on links to see where they will take you. You begin to build a list of your favorite websites so that you can find your way back to them. All this is taken for granted, but the browser is more than just a simple window on the world.
The pages that you visit with your browser are not like the pages in a book or a magazine. They do not really exist as you see them outside of your browser window. A page that you may visit on the Internet is really a set of instructions telling your browser how to build the page that you see.
The pictures that you see exist as separate files on the web server. The text that you see may be contained within the instruction set or may be a separate file. There may be other components of the page that are contained in still other files on the server.
When you call for a page by clicking a link or typing a URL into the address bar at the top of your browser, your browser requests the blueprint for the page. It checks the blueprint and requests any other files that it will need to complete the page building project. It then follows the blueprint and produces the page that you see on your computer.
There will be an html file, that is the basic blueprint file or instruction set, often there will be a stylesheet that contains further instructions about the presentation of the page, there may be media files such as pictures, and there may be other auxiliary files that are required to produce the page. A simple page of text may be just the one html file but most pages require some supporting files.
Everything that moves over the web is encoded to ones and zeros. The images that you see on your screen is a representation of the information contained in the digital file. The file contains information about the color of each dot or pixel in the picture. The browser converts this information to something that you can see and provides it to your video driver to paint the picture on your monitor screen.
Most of us use a standard browser to view web pages. There are other types of browsers that are available. There are aural browsers for the visually impaired that act as screen readers and provide an audio output 'reading' the content of the page. There are text only browsers that disregard any pictures or other media files.
The browser is your window into the world of the Internet. With your browser you can view any pages that are available anywhere in the world. It is the magic carpet that can take you anywhere that you want to go.