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5. The advantages of creating one large page are that one file is easier to maintain, the links don`t break, and it mirrors real-world document structure. The disadvantages are that it has a longer download time, visitors have to scroll a lot, and the structure is rigid and too linear. Exercises 1. Try your hand at reworking the example shown in Figure 16.5. Organize the information into a definition list or a table. Make it easy for the visitor to scan for the important points on the page. 2. Try the same with the example shown in Figure 16.7. How can you arrange the information so that it`s easier to find the important points and links on the page? file:///G|/1/0672328860/ch16lev1sec8.html (3 von 3) [19.12.2006 13:49:54] Lesson 17. Designing for the Real World In previous lessons, you learned about what you should and shouldn`t do when you plan your website and design your pages. You also learned about what makes a good or bad website. There`s another important factor that you should take into consideration, and that`s how to design your pages for the real world. You`ve already learned that the real world consists of many different users with many different computer systems who use many different browsers. Some of the things we haven`t yet addressed, however, are the many different preferences and experience levels that the visitors to your site will have. By anticipating these real-world needs, you can better judge how you should design your pages. I`ll also explain how you can make sure that your websites are usable people who are disabled and must use accessibility technologies to browse the Web. In this Lesson In today`s lesson, you`ll learn some ways that you can anticipate these needs, as well as the following: ● Things to consider when you`re trying to determine the preferences of your audience ● Various ways of helping users find their way around your site ● HTML code that displays the same web page in each of the XHTML 1.0 specifications (Transitional, Frameset, and Strict) ● What accessibility is, and how to design accessible sites ● Using an accessibility validator file:///G|/1/0672328860/ch17.html [19.12.2006 13:49:55] What Is the Real World, Anyway? You`re probably most familiar with surfing the Internet on a computer that runs a specific operating system, such as Windows, Mac OS X, or something similar. You may think you have a pretty good idea of what web pages look like to everyone. Throughout this book, you`ve learned that the view you typically see on the Web isn`t the view that everyone else sees. The real world has many different computers with many different operating systems. Even if you try to design your pages for the most common operating system and the most common browsers, there`s another factor that you can`t anticipate: user preference. Consider the following family, for example: ● Bill is a top-level executive at a Fortune 100 company that has its own intranet. Almost everyone in the company uses the same operating system and the same browser. Bill is used to seeing the Internet as mostly text, with a smattering of images here and there to stress informational pointsa lean and mean Web with very little multimedia and a lot of information. He finds all the extra glitz annoying and inconvenient to download, so he turns off JavaScript and Flash. ● Bill`s wife, Susan, has never used a computer before, but she has always wanted to learn. She`s a genealogist by hobby and has learned that the Internet has many resources in that field. She also wants to publish her family history on the Web. When she and her husband got their cable modem hooked up, she was thrilled. But soon she was asking questions such as, "Can we fit more on the screen? Those letters are a bit too small...can we make them larger? Where are the pictures? How come you have the music turned off? It says that there`s sound on this page!" She already wanted to see the Internet much differently than what her husband was used to seeing. ● Bill and Susan have a son, Tom, who`s in high school. He`s an avid gamer and wants to see special effectsglitz, multimedia! He pumps up the volume as loud as he can and pushes the capacities of their new computer to the max. He also thinks "Browser X" is better than "Browser Y" because it supports lots of cutting-edge features. He wants to design a website that provides hints, tips, and tricks for one of his favorite online games. ● Tom`s older sister, Jill, is an art major in college, studying to be a commercial artist. She has a keen interest in sculpture and photography. She plans to use her new computer for homework assignments, so she`ll be looking at the Web with a keen visual interest. She wants to view her pages in true color, in the highest resolution possible. ● Then there are the senior members 533 the family, Susan`s aging parents, who have recently moved in with the family after years of living in a rural town. Their experience with computers is minimalthey`ve only seen them in stores. They`re interested in learning so that they can view family photos online and exchange email with out of town relatives, but Dad`s eyes aren`t quite as sharp as they used to be. He needs a special browser so that he can hear the text as well as see it. All these people are using the same computer and operating system to view the Web. In all cases but one (young Tom), they`re also using the same browser. This example illustrates one of the other things that you need to think about when you design your website: the needs of the users themselves. Some of these needs are easier to accommodate than others. The following section describes some of the considerations you saw in the previous example. file:///G|/1/0672328860/ch17lev1sec1.html [19.12.2006 13:49:55] Considering User Experience Level There are varied levels of experience in our fictitious family. Although everyone is keenly interested in the Web, some of them have never even seen a Web browser before. When you design your site, you should consider that the people who visit it might have varying levels of experience and browsing requirements. Will the topics that you discuss on your site be of interest to people with different levels of experience? If so, you might want to build in some features that help them find their way around more easily. The key, of course, is to make your navigation as intuitive as possible. By keeping your navigation scheme consistent from page to page throughout the site, you`ll do a favor for users of all experience levels. There are a number of features you can add to your site that will improve its usability for everyone. Add a Search Engine Many users go straight to the search engine when they want to find something on a site. No matter how much time and effort you put into building a clear, obvious navigation scheme, someone looking for information about Frisbees is going to look for a box on your page where they can type in the word "Frisbee" and get back a list of the pages where you talk about them. Unfortunately, locating a good search engine package and setting it up can be an awful lot of work, and difficult to maintain. On the other hand, there are some alternatives. Some search engines enable you to search a specific site for information. You can add a link to them from your site. Some search engines even allow you to set things up so that you can add their search engine to your site, such as Google: http://www.google.com/services/free.html By signing up, you can add a search box to your site that enables your users to search only pages on your own site for information. For a list of other ways to add search functionality to your site, see the following page in the Mozilla Directory: http://dmoz.org/Computers/Software/Internet/Servers/Search/ Use Frames Wisely One failing of some HTML books is that they tell you about all the different techniques you can use to create Web pages, but they don`t offer any comparative information that explains when and how these techniques ought to be used. For example, I`ve devoted a number of pages to discussing frames, but the fact is that they should really be used only when nothing else will work. For example, putting all of your navigation in one frame and your content in another just because you can is generally a poor idea. Frames have a couple of specific disadvantages that make them unsuitable for use in many cases. The first is that they make it hard for users to bookmark inner pages on sites. If your entire site is a frameset, the URL in the user`s location bar never changes as the user navigates within the site. When the user gets to your inner page that has a wonderful recipe for chocolate chip cookies that your grandmother gave you, he`ll have a hard time bookmarking it because his browser wants to bookmark the top-level frameset itself. When he returns on future visits, he`ll be taken back to your home page. The second issue that`s common with framesets is that they can interfere with search engines. Again, if your entire site is inside a frameset, when a search engine fetches your home page, it`s probably going to get a page with no real content to speak of. Then, it will download, say, the navigation frame, which file:///G|/1/0672328860/ch17lev1sec2.html (1 von 4) [19.12.2006 13:49:56] lacks context, the content frame, which may lack header and footer information, and on and on. If you want people to be able to find your site using search engines, frames can get in your way. There are also other issues people have had with framesets in the past, like problems printing and problems with the back button. Browsers mostly compensate for these issues today, but even so, frames can confuse your users. In some cases, there`s just no other good way to attack a problem, but you should always make sure that there`s not a better way before going the frames route. Use Concise, Sensible URLs One common mistake made by web designers is not considering how users share URLs. If your site is interesting at all, people are going to email the URL to their friends, paste it into instant messaging conversations, and talk about it around the water cooler. Making your URLs short and easy to remember makes them that much easier for people to share. There`s a reason why people have paid huge sums for domain names like business.com and computers. com in the past. They`re easy to remember and you don`t have to spell them out when you tell them to people. You may not have any control over your domain name, but you can exercise control over the rest of your URLs. Say that you have a section of your site called "Products and Services." All the pages in that section are stored in their own directory. You could call it any one of the following: /ps /prdsvcs /products /products_services /products_and_services There are plenty of other options as well (you could call it /massapequa if you wanted to), but the preceding list seems like a reasonable group of options. Of the list, a few stand out to me as being poor choices. /products_service and /products_and_services just seem too verbose. If the pages under those directories have long names at all, you`re suddenly in very long URL territory, which isn`t conducive to sharing. On the other hand /prdsvcs may be short, but it`s also difficult to remember, and almost certainly has to be spelled out if you tell it to anyone. It`s probably no good. That leaves two remaining choices: /ps and /products. The first, /ps, is nice and short, and probably easy to remember. Using it would be fine. However, there`s one other principle of URLs that I want to talk aboutguessability. Chances are that most of the people who visit your website have been using the Web for awhile. There`s some chance that they might just assume that they know where to go on your site based on experience. If they want to read about your products, they may guessbased on their experience with other sites they`ve visitedthat your products will be listed at http://www.your-url.com/products. Any time you can put your content where your users will assume it to be, you`re doing them a favor. Using standard directory names such as /about, /contact, and /products can make things ever so slightly easier for your users at no cost to you. My final bit of advice on URLs is to make sure that they reflect the structure of your site. One time, I worked on a site that consisted of hundreds of files, all in a single directory. The site itself had structure, but the files were not organized based on that structure. Whether the user was on the home page or five levels deep within the site, the URL was still just a filename tagged onto the hostname of the server. Not only did this make the site hard to work on, but it also kept some useful information away from users. Let`s say you have a site about cars. What`s more useful to your users? This: file:///G|/1/0672328860/ch17lev1sec2.html (2 von 4) [19.12.2006 13:49:56] ... - tailieumienphi.vn
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