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• Table of Contents• Reviews• CD-ROM• Reader Reviews• Errata• AcademicDreamweaver MX 2004: The Missing ManualBy
David Sawyer McFarland Publisher: O''ReillyPub Date: February 2004ISBN: 0-596-00631-4Pages: 840Slots: 1.0
Dreamweaver MX 2004: The Missing Manual
enables both first-time and experienced web designers to
bring stunning, interactive web sites to life. What sets
this new edition apart is the crystal-clear writing, welcome
humor, and exclusive features. With over 500 illustrations,
a handcrafted index, and the clarity of thought that has
made bestsellers of every Missing Manual to date, this new
edition is the ultimate atlas for Dreamweaver MX 2004.
15.8 Download Statistics
Remember the joke that WWW really stands for "World Wide Wait"? Even as more
and more people upgrade to speedy DSL and cable modems, file size is the constant
foe of the Web designer. What takes only a moment to load from your computer's
hard drive could take minutes to travel across the Internet. The more information
you put into a Web page, the more time it will take to load.You can judge how big your page is, and therefore how long it will take to download,
by looking at the download stats in the status bar at the bottom of the document
window. You'll see something like this: 5k/2 sec.The first bit of information tells you the total size of your Web page and any files
included in the page. That's an extremely helpful statistic, because even though a
Web page document itself may only be 1 K in size, a 20 K GIF image actually blows
it up to 21 K.Next to the file size, you see how long, in seconds, it will take to download the Web
page and all its graphics and other elements. Of course, each visitor's connection speed
may be different, depending on whether she's using a cable modem, gas-powered
14.4 Kbps dial-up modem, or whatever. Out of the box, Dreamweaver calculates this
figure based on the time it would take a 28.8 Kbps modem to download the page.
(This is a best-case calculation, representing a world where there's no Internet traffic
or network problems.)
GEM IN THE ROUGHCaching InBehind the scenes, Web browsers store the graphics they download onto the computer's hard drive. This is a speed trick. If you click your Back button to return to a Web page whose graphics files the browser has already downloaded, the browser simply pulls them out of the cacheoff the hard drive, in other wordsinstead of re-downloading them. This arrangement makes the page load more quickly, since the hard drive is generally much faster than the modem.As a Web designer, you can capitalize on this standard Web-browser feature by reusing the same graphics files on more than one page of your site. For instance, you might create a navigation bar composed of small graphic buttons (Home, Contact Us, Products, and so on). If you reuse those buttons on other pages of the site, those pages will appear to download more quickly.This same trick works for external CSS style sheets. A browser needs to download a complete style sheet with hundreds of formatting commands only once for any page on a site to reuse it. By putting all of your formatting into one or more external files, you can keep your Web pages mean and lean.If you do capitalize on this trick, be aware that the download stats in Dreamweaver's status bar may not reflect the added speed boost that's provided by cached files. |
window by choosing Edit Sizes from the status bar's window-size pop-up menu. Alternatively,
choose Edit
Preferences and click the Status Bar category of the Preferenceswindow; either way, proceed as described in Figure 15-16.NOTEPeople hate to wait. You may think that the graphic design of your Web site is so compelling that even
if it takes a full minute to download that zippy new Flash home page, people will stick around.Think again. Research shows that 10 seconds is the maximum amount of time that someone will stay focused
on a task while waiting. That means if you're designing a Web site for people with 56 Kbps modems, keep
your pages below about 45 K.In this dialog box, you can
change the connection speed
that Dreamweaver uses in
calculating how long your
page will download. A 34 K
Web page will take at least
10 seconds to download over
a 28.8 Kbps modem. But if
you choose 56 Kpbs from the
pull-down menu, the status
bar lists the download time as
5 seconds. Choose the connection
speed that you think
most visitors to your site will be
using. When you aren't sure,
err on the side of caution by
using a lower speed, and keep
in mind that Dreamweaver's
calculations are on the optimistic
side.
