html css the complete reference 5th edition

www.it-ebooks.info HTML & CSS: The Complete Reference, Fifth Edition www.it-ebooks.info About the Author Thomas A. Powell (tpowell@pint.com) is a long-time industry veteran. After an early stint at CERFnet in the early ‘90s, he founded Powell Internet Consulting (later renamed PINT) in 1994, a Web design and consulting services firm. Today, PINT (pint.com) provides Web development, design, and consulting services to large and small corporations all over the United States in a variety of industries. Beyond his involvement at PINT, Thomas is heavily involved in the academic community. He developed the University of California, San Diego Extension Web Publishing program in the late 1990s and continues to teach classes there in Web development and design. He is also an instructor for the UCSD Computer Science Department, where he teaches classes in Web development and the theory of programming languages. Mr. Powell is well published, and his work has appeared in numerous trade publications. He continues to publish regularly in Network World. He also has published numerous books on Web technology and design, including Ajax: The Complete Reference, JavaScript: The Complete Reference, and many others. His books have been translated into over 12 languages and are used around the world both in industry and college settings. About the Technical Editor James H. (Jim) Pence is a full-time writer, editor, speaker, singer, and performance chalk artist. Jim broke into book publishing in 2001 with How to Do Everything with HTML, a how-to book on Web authoring, written “by a nontechie for nontechies,” and published by McGraw-Hill Professional. He followed this book the same year with another book for McGraw-Hill: Cascading Style Sheets: A Beginner’s Guide. McGraw-Hill published a second edition of Jim’s HTML book, re-titled How to Do Everything with HTML & XHTML, in 2003. Jim is also a published novelist. He is the author of Blind Sight (Tyndale, 2003), a suspense/thriller novel set in the mind-control cults, and The Angel (Kregel, 2006), set against the backdrop of the euthanasia and physician-assisted suicide movements. Jim moved into “true crime” writing with his latest book, Terror by Night (Tyndale, 2009). Terror by Night is the true story of the brutal 2008 murders of the Caffey family in Emory, Texas. You can learn more about Jim’s books and other creative projects at his Web site: www.jamespence.com. www.it-ebooks.info HTML & CSS: The Complete Reference, Fifth Edition Thomas A. Powell New York Chicago San Francisco Lisbon London Madrid Mexico City Milan New Delhi San Juan Seoul Singapore Sydney Toronto www.it-ebooks.info Copyright © 2010 by The McGraw-Hill Companies. All rights reserved. Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher. ISBN: 978-0-07-174170-5 MHID: 0-07-174170-4 The material in this eBook also appears in the print version of this title: ISBN: 978-0-07-149629-2, MHID: 0-07-149629-7. All trademarks are trademarks of their respective owners. Rather than put a trademark symbol after every occurrence of a trademarked name, we use names in an editorial fashion only, and to the benefit of the trademark owner, with no intention of infringement of the trademark. Where such designations appear in this book, they have been printed with initial caps. McGraw-Hill eBooks are available at special quantity discounts to use as premiums and sales promotions, or for use in corporate training programs. 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Except as permitted under the Copyright Act of 1976 and the right to store and retrieve one copy of the work, you may not decompile, disassemble, reverse engineer, reproduce, modify, create derivative works based upon, transmit, distribute, disseminate, sell, publish or sublicense the work or any part of it without McGraw-Hill’s prior consent. You may use the work for your own noncommercial and personal use; any other use of the work is strictly prohibited. Your right to use the work may be terminated if you fail to comply with these terms. THE WORK IS PROVIDED “AS IS.” McGRAW-HILL AND ITS LICENSORS MAKE NO GUARANTEES OR WARRANTIES AS TO THE ACCURACY, ADEQUACY OR COMPLETENESS OF OR RESULTS TO BE OBTAINED FROM USING THE WORK, INCLUDING ANY INFORMATION THAT CAN BE ACCESSED THROUGH THE WORK VIA HYPERLINK OR OTHERWISE, AND EXPRESSLY DISCLAIM ANY WARRANTY, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. McGraw-Hill and its licensors do not warrant or guarantee that the functions contained in the work will meet your requirements or that its operation will be uninterrupted or error free. Neither McGraw-Hill nor its licensors shall be liable to you or anyone else for any inaccuracy, error or omission, regardless of cause, in the work or for any damages resulting therefrom. McGraw-Hill has no responsibility for the content of any information accessed through the work. Under no circumstances shall McGraw-Hill and/or its licensors be liable for any indirect, incidental, special, punitive, consequential or similar damages that result from the use of or inability to use the work, even if any of them has been advised of the possibility of such damages. This limitation of liability shall apply to any claim or cause whatsoever whether such claim or cause arises in contract, tort or otherwise. www.it-ebooks.info Contents at a Glance Part I Core Markup 1 Traditional HTML and XHTML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2 Introducing HTML5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 3 HTML and XHTML Element Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 Part II Core Style 4 Introduction to CSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429 5 CSS Syntax and Property Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 521 6 CSS3 Proprietary and Emerging Features Reference . . . . . . . . . . . . . . . . . . 613 Part III Appendixes A Character Entities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 727 B Fonts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 751 C Colors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 765 D URLs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 783 E Reading a Document Type Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 801 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 809 v www.it-ebooks.info This page intentionally left blank www.it-ebooks.info Contents Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxi Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxiii Part I Core Markup 1 Traditional HTML and XHTML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 First Look at HTML and XHTML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Hello HTML and XHTML World . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Viewing Markup Locally . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Viewing Markup with a Web Server . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 HTML and XHTML: Version History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 HTML and XHTML DTDs: The Specifications Up Close . . . . . . . . . . . . . . . . 16 Document Type Statements and Language Versions . . . . . . . . . . . . . 18 (X)HTML Document Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 The Document Head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 The Document Body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Browsers and (X)HTML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Validation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 The Doctype Switch and Browser Rendering Modes . . . . . . . . . . . . . 39 The Rules of (X)HTML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 HTML Is Not Case Sensitive, XHTML Is . . . . . . . . . . . . . . . . . . . . . . . 41 Attribute Values May Be Case Sensitive . . . . . . . . . . . . . . . . . . . . . . . . 42 (X)HTML Is Sensitive to a Single Whitespace Character . . . . . . . . . . 42 (X)HTML Follows a Content Model . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Elements Should Have Close Tags Unless Empty . . . . . . . . . . . . . . . . 43 Unused Elements May Minimize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Elements Should Nest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Attributes Should Be Quoted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Entities Should Be Used for Special Characters . . . . . . . . . . . . . . . . . . 44 Browsers Ignore Unknown Attributes and Elements . . . . . . . . . . . . . 44 Major Themes of (X)HTML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Logical and Physical Markup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Standards vs. Practice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Myths and Misconceptions About HTML and XHTML . . . . . . . . . . . 47 The Future of Markup—Two Paths? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 XHTML: Web Page Markup XML Style . . . . . . . . . . . . . . . . . . . . . . . . 49 HTML5: Back to the Future . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 2 Introducing HTML5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Hello HTML5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Loose Syntax Returns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 XHTML5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 vii www.it-ebooks.info viii HTML & CSS: The Complete Reference viii HTML & CSS: The Complete Reference HTML5: Embracing the Reality of Web Markup . . . . . . . . . . . . . . . . . . . . . . . 62 Presentational Markup Removed and Redefined . . . . . . . . . . . . . . . . . . . . . . 63 Out with the Old Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 In with the New Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 Sample of New Attributes for HTML5 . . . . . . . . . . . . . . . . . . . . . . . . . 66 HTML5 Document Structure Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 Adding Semantics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Marking Text . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Indicating Dates and Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 Inserting Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 Specifying Navigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 HTML5’s Open Media Effort . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 <video> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 <audio> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 Media Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 Client-Side Graphics with <canvas> . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 Drawing and Styling Lines and Shapes . . . . . . . . . . . . . . . . . . . . . . . . 85 Drawing Arcs and Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90 Scaling, Rotating, and Translating Drawings . . . . . . . . . . . . . . . . . . . . 93 Using Bitmaps in Drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 Text Support for canvas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 <canvas> Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 HTML5 Form Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 New Form Field Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 Validating Data Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 Autocomplete Lists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 Miscellaneous Usability Improvements . . . . . . . . . . . . . . . . . . . . . . . . 105 Emerging Elements and Attributes to Support Web Applications . . . . . . . . 106 menu Element Repurposed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 command Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 meter and progress Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 details Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 output Element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 The Uncertain Future of Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 The draggable Attribute and the Drag and Drop API . . . . . . . . . . . . 112 contenteditable Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 spellcheck Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 Internationalization Improvements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 HTML5 Metadata Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 data-X Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 Microdata . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117 HTML5: Beyond Markup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 defer Attribute . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121 HTML, JavaScript, and the DOM Renewed . . . . . . . . . . . . . . . . . . . . . 121 Standardizing and Extending Ad Hoc JavaScript Conventions . . . . 125 Major HTML5 Themes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 HTML5 Today or Tomorrow? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 HTML5 as a Catch-All . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 HTML5: Web Politics as Usual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 HTML5: Imperfect Improvement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 www.it-ebooks.info 3 HTML and XHTML Element Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 Flavors of HTML and XHTML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 Core Attributes Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 class . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 id . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 style . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 title . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 Language Attributes Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 dir . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 lang . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 Other Common Attributes Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 accesskey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 align . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 contenteditable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 datafld . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 dataformatas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 datasrc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 disabled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 hidefocus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 hspace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 tabindex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 unselectable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 vspace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 width . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 Common HTML5 Attributes Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 accesskey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 contenteditable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 contextmenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 data-X (Custom Data Attributes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 draggable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 hidden . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 itemid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 itemprop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 itemref . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 itemscope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 itemtype . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 spellcheck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 tabindex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 Event Attributes Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 HTML5 Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 Internet Explorer’s Extended Event Attributes . . . . . . . . . . . . . . . . . . 147 HTML Element Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154 <! > (Comment) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155 <! .[ ] > (Conditional Comment) . . . . . . . . . . . . . . . . . . . . . . . . . . 155 <!DOCTYPE> (Document Type Definition) . . . . . . . . . . . . . . . . . . . 157 <a> (Anchor) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 <abbr> (Abbreviation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164 <acronym> (Acronym) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 C o n t e n t s ix www.it-ebooks.info [...]... indicates the particular version of HTML or XHTML being used in the document The first example uses the strict 4.01 specification, the second uses a reduced form for HTML5 the meaning of which will be explained a bit later on, and the final example uses the XHTML 1.0 strict specification • The , , and tag pairs are used to specify the general structure of the document The required... inclusion of the xmlns attribute in the tag is a small difference required by XHTML • The tag used in the examples indicates the MIME type of the document and the character set in use Notice that in the XHTML example, the element has a trailing slash to indicate that it is an empty element • The and tag pair specifies the title of the document, which generally appears in the title... and standards issues There just isn’t a step-by-step cookbook for each element or property Given the maturity of the Web industry, we aimed not for the complete tutorial, but instead for the complete reference It should go without saying that more markup changes to HTML and CSS are inevitable HTML5 , in particular, is a complete moving target, and rather than punting on it, we took the best shot at its... get back to the book. < /html> O NLINE http://htmlref.com/ch1 /html4 helloworld .html A simple modification of the initial line is really all that is necessary to make this an HTML5 example, the comment and text is changed so you can keep the examples straight: Hello HTML5 World... really isn't so hard either! Soon you will ♥ using XHTML too. There are some differences between XHTML and HTML but with some precise markup you'll see such differences are easily addressed. < /html> O NLINE http://htmlref.com/ch1/xhtmlhelloworld .html The preceding examples use some of the most common elements used in (X )HTML documents, including: • The statement,... example: Hello XHTML World Welcome to the World of XHTML XHTML really... HTML5 World HTML5 example > Welcome to the Future World of HTML5 HTML5 really isn't so hard! www.it-ebooks.info Chapter 1: Tr a d i t i o n a l H T M L a n d X H T M L O NLINE http://htmlref.com/ch1 /html5 helloworld .html In the case of XHTML, which is a form of HTML that is based upon the syntax rules of XML, we really don’t... the content; otherwise, it is an all-new effort Most obviously, as compared to the previous editions, which focused mainly on XHTML and HTML 4, this edition focuses on HTML5 , which represents both a return to the markup past and the unveiling of an exciting future of Web applications However, we do retain some information from previous editions because in order for this work to be truly complete, we... behind the scenes However, in the case of Web documents, markup in the form of traditional Hypertext Markup Language (HTML) and its Extensible Markup Language (XML)-focused variant, XHTML, is a little more obvious These not-so-behind -the- scenes markup languages are used to inform Web browsers about page structure and, some might argue, presentation as well First Look at HTML and XHTML In the case of HTML, ... Hello HTML 4 World HTML 4.01 strict example > Welcome to the World of HTML HTML really isn't so hard! Soon you will ♥ using HTML. . . . . . . 166 C o n t e n t s ix www.it-ebooks.info x HTML & CSS: The Complete Reference x HTML & CSS: The Complete Reference <address> (Address) . . . . . . . . . . . . . . . 371 C o n t e n t s xi www.it-ebooks.info xii HTML & CSS: The Complete Reference xii HTML & CSS: The Complete Reference <spacer> (Extra Space) . . . . . . . . . . . . 545 C o n t e n t s xiii www.it-ebooks.info xiv HTML & CSS: The Complete Reference xiv HTML & CSS: The Complete Reference background-repeat . . . . . . . . . . . . . . .