As we explain programming for the web to you, it’s helpful for all of us to speak the same language, at least when it comes to the subject at hand. Knowing how the web works, at least at a high level, will pay dividends when you start creating sites that will work on it. Granted, you don’t need to know how a car works before driving, but knowing how the steering wheel, throttle, and brakes all relate to make the vehicle move is especially important to keep you from hitting things. So consider what you’re about to read as driver’s education for web programming. The difference is that at the end you don’t have to buy insurance
Understanding How the Web Works
The World Wide Web consists of a large group of computers, known as servers that exist solely to provide information when that information is requested. The information is requested by a piece of computer software called a web browser. If you’re here, you’ve almost certainly used the web countless times already, maybe even to order this book.
The web browser
When a client requests a web page, a web browser such as Microsoft Internet Explorer or Mozilla Firefox (or Safari or Google Chrome or Opera or Lynx) is used. The web page itself can be a document stored on your computer, just like a word processing document. A program like Microsoft Word knows how to open documents formatted for Microsoft Word. In the same way, a web browser knows how to open documents formatted for the web. More on this later.
Several popular web server software packages are available, but two stand out above the rest: Apache hatted and Microsoft Internet Information Services (IIS). Between the two of them, these server software packages are responsible for hosting the vast majority of all web domains.