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| Introduction To Web Browsers |
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Browser Tips & Tricks February 2001 • Vol.9 Issue 2 Page(s) 99-100 in print issue |
Introduction To Web Browsers A Look At How Web Pages Get To Your Computer Screen | ||
 It is hard to imagine going a day without browsing the World Wide Web. We take for granted all of the information the browser helps make available to us: stock quotes, weather forecasts, music, videos, and current news, just to name a few. Not long ago, it took quite a bit of work to get this information, and it wasn't nearly as fresh and up to date. A lot has happened in a relatively short time to make this information easy to access. One thing that happened is the Web browser. If it weren't for the creation of the World Wide Web and the browsers that read Web pages, the Internet would still be a novelty used primarily by the people in the academic and military worlds. Not many people would want to surf the Web if it consisted only of text and text links. The graphics of a Web page and the convenience and interactivity that using a mouse to navigate it are what keep users coming back for more. In short, the browser made the Internet accessible.  Browser Basics. So how does this important gateway to the Web work? To understand how the browser works, you must first understand some of the underlying technology that makes the Web work. While working with CERN (a European center for physics research) in Geneva, Switzerland 11 years ago, Tim Berners-Lee came up with an idea to let people share their knowledge and work by means of an intertwined web of hypertext-connected documents. This project, called the WWW (short for World Wide Web), began in 1989. By October of 1990, Berners-Lee had written the first Web server and Web client. Hypertext. The key to the Web is hypertext, which wasn't a new concept in 1989. In fact, the term was coined by hypertext pioneer Ted Nelson in the mid 1960s. Hypertext connects documents, in this case Web pages, to each other based on common traits called hyperlinks. On the Web, a hyperlink is an area of a Web document that, when clicked, refers you to another document. For example, linked text on a Web page is underlined, denoting the link. If you click a hyperlink labeled "Contact Information," that hyperlink should open a new document displaying contact information. Common protocols. When Berners-Lee began developing his first Web products, Unix was the networking system of choice. By default, TCP/IP (Transmission Control Protocol/Internet Protocol; the language governing computer communication on the Internet) became the PC-to-PC connectivity protocol of choice because it was native to Unix, and all of the universities and government agencies already had it in place. That's why all Web servers and browsers run over TCP/IP and why TCP/IP has become the de facto standard around the globe. While TCP/IP provides machine-to-machine connectivity, Web browsers run their own protocol over this link. This special protocol is the Hypertext Transfer Protocol; it's the reason for the "http" prefix you are used to seeing in a Web page's address. HTTP provides the mechanism for retrieving pages from Web servers and loading them in your browser's window. The first Web server only served pages of hyperlinked text to the browser. There were no rollover buttons or animated characters; in fact there were no graphics at all. While things have changed radically since that first release, the overall concepts of the Web page and browser remain the same. The Making Of A Web Page. A Web page is actually just a text document arranged in a specific set of tags. A tag is a code or symbol that tells a Web page how to be formatted. Among other things, these tags define the beginning and the end of the Web page; whether text should be bolded, italicized, or underlined; if the text or image is a hyperlink; and if a graphic should be displayed. To mark up a text document with these tags is to apply the rules of HTML (Hypertext Markup Language). All Web pages are written in HTML. Typically, tags come in pairs: a start tag and an end tag, each surrounded by < > signs. For example, <html> (the start tag) and </html> (the end tag) is the pair of tags that you need to define the beginning and ending of every Web page. The forward slash (/) in the end tag differentiates the two tags. Some tags, however, such as image and hyperlink tags, do not need an identical end tag. Web pages today, just like those of 10 years ago, are nothing more than text documents marked up with hundreds of tags that define how the page will look and refer to other objects or pages. If you want to see a Web page's HTML tags, you can do so by choosing View, Source in Internet Explorer, NeoPlanet, and Opera. In Netscape, choose Page Source from the View menu. Now you will see the text document and all the tags that make it a Web page. As you will see, writing all of that code by hand is a monumental task. Before graphical HTML tools became available, all Web coding was done using nothing more than a text editor. From Text Tags To Web Pages. So how does this text document go from being a text document to an interactive Web page filled with graphics and other things? That's where the browser comes in. The job of the browser is to interpret the HTML document and display it to you as a Web page. The browser actually reads the text document, looks at all of the tags, and interprets them according to the rules defined by the W3C (World Wide Web Consortium). Among other things, the W3C establishes HTML standards for all Web page developers. How well the developers adhere to the recommendations of the W3C determines how well browsers interpret a document. That's why some pages look one way with a Netscape browser and a different way with a Microsoft browser. It all comes down to how the browsers handle the tags.
Here is what a simple Web page looks like with the most basic tags: <html> <head> <title>Smart Computing Sample Web Page</title> </head> <body> This is where the content for the page would go. <p><ahref="camera.htm"><img border="0"src="Images/Baloons.jpg" usemap="#FPMap0"></a></p> Above this line is a graphic. Note the <img> tag does not require a closing tag. The <a href=> tag gives us the hyperlink's destination, while the <img and src> tag tells us the location of the graphic that is going to be displayed for the hyperlink. </body> </html> Note the tag pairs throughout the page. Many more tags can and do go into the body section of a Web page, including tags for tables, font styles, and other formatting. Choose A Browser. Believe it or not, you have many choices when it comes to what browser you want to use to surf the Web; you don't have to stick with the one that comes with your operating system. Some browsers are platform specific, which means they only work on Sun Solaris or BeOS systems. Other browsers, such as Opera, work on multiple platforms. Microsoft and Netscape are the two companies that dominate the browser market. These two vendors account for about 94% of the browser market, with Microsoft's Internet Explorer claiming 76% of that total. Two other popular browsers, Opera and NeoPlanet, split much of the remaining market share. Even though these numbers indicate that Microsoft has a hold on the browser market, don't turn your back on other browsers just yet. This market is continually shifting, and to shake things up a bit, Opera announced on Dec. 1, 2000 its plan to release Opera 5 for Windows. This will be Opera's first free browser, so it may change some things in the browser wars. So which browser should you choose? Just because your PC came preloaded with one vendor's browser, don't think you are stuck with it. Check out some other browsers to see if you prefer the way a different browser works. Also, keep in mind that you don't have to choose just one browser. It's very easy to have two or three browsers on your PC at one time. In fact, it's a good idea to have a couple different browsers on your PC. That way, if one browser can't display a certain page, you can try to view the page with the other browser. No Thanks, I'm Just Browsing. The Web browser has evolved quite a bit from its humble beginnings. Not only does the browser now let you view text and graphics, you can also view streaming multimedia and interact with a Web site. The browser makes the Web accessible and fun so that surfing for information is a delight rather than a chore.  by Keith Schultz |
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