Get "just the facts" on beginning XML in this complete practitioner's guide, whether or not HTML or SGML is new to the user. Concrete examples illuminate each key aspect of XML development throughout the book.
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XML promises to structure and deliver data within the next generation of Web browsers. Understanding XML can be difficult, but John Simpson's guide explains it with style, simplicity, and wit, showing what XML is and how it works.
Early on, the author places XML in context of the HTML and SGML Web standards and explains its advantages for sending virtually any type of content over the Internet--regardless of what that data may be. (In XML, designers literally define their own tags and rules for the data.) The author's choice of content is original--his "FlixML" sample XML uses old movies (in particular, classic Hollywood B movies) as its focus. This entertaining approach doesn't skimp on the real details of XML, however, which suggests how flexible XML is. (For the true film buff, Just XML also includes several short reviews of some of the author's favorite B movies.)
On technical matters, Just XML exposes some XML features such as XLink and XPointers, as well as cascading style sheets. The author surveys some of the tools that let you work with XML right now. This guide combines good technical knowledge with a winning approach to an important and powerful Internet standard. --Richard DraganFrom the Inside Flap:
Why did I write Just XML? It's a fair question. (And I won't even ask you in return to address its obvious flip side: Why are you reading it? I hope to answer that for you in a moment.) The short answer is that I wrote this book because I work with computers every day and want them to be more useful than they already are. I want them to be more useful not just for me; every week I meet a hundred-odd people (some of them quite odd, but that's a subject for a different book) who are baffled by the failure of computers to "think" the same way we do. A longer, more precise answer is that I want the Internet to be more useful: When I type a keyword or phrase in a Web search engine, I don't want a list of ten thousand alleged "hits" returned, sorted by a relevance that some machine has calculated based on some algorithm that may or may not have much to do with the documents' actual substance. I want the Internet and its associated technologies to be smart about all the information it holds: to understand itself, I guess you might say. And I believe that the Extensible Markup Language, or XML, is the surest route to that ideal right now and the faster it spreads, the faster we'll get there. Which brings us to a natural corollary: Why, specifically, might you want to read Just XML as opposed or in addition to a hundred other books on the same topic?
WHY JUST XML?
Let's break that section heading into two separate questions: "Why 'just'?" and "Why XML?" And let's consider the second question first.
Unless you've been in a technological fog for the last five years or so, you already know that the Internet particularly the part of it called the World Wide Web has taken the developed world by storm. Everyone from the largest multinational corporation to the neighborhood butcher lists his or her own companyname in the Yellow Pages. It's leached into the daily lives not just of corporate and government entities, but even of everyday people (school-age children have their own home pages). You may know also that what underlies all the Web's exhilarating breadth of content and style is a simple secret, not exactly a dirty one, but one still capable of shocking innocent newcomers: It's all just text. (Well, all right: it's not all text. Obvious exceptions include image, sound, and other multimedia files. However, the instructions to the browser about how to display this non-textual information are indeed like the other 90% of the Web's content plain old ASCII.) Regular text is bracketed with special strings of other text that instructs a user's browser to render the enclosed matter in some particular style. For example, the tags (as these bracketing strings are called) and say, "Render everything between the opening and the closing in an emphasized form." (What "emphasized" means is left up to the browser, but it almost always means italicized.) You don't need any exotic software to create these marked-up text files, although such software is certainly available; all you need is a plain old text editor such as Windows Notepad or UNIX vi and a facility for getting at the , and / keys without breaking your train of thought. That's all well and good, as my grandmother might have said, but it doesn't go far enough. I'll give you some detailed reasons why in Chapter 1, "Markup Laid Down," but for now, just take it on faith that the Web's established markup language Hypertext Markup Language, or HTML fails to establish meaning for elements of the documents in which it's written. Furthermore, if you're creating your Web files in Tokyo, you'd better forget about using that nifty new Kanji keyboard: HTML makes easy use of only the characters in the Roman alphabet letters A through Z and digits 0 through 9. XML easily bests HTML on both counts.
Now about that "just" in the title:
As you'll see, XML shares some of HTML's bloodlines. Many of the folks responsible for getting HTML off the ground, as well as its decades-old parent SGML (Standardized General Markup Language), were involved in the development of the XML standard, too. But both HTML and SGML are different beasts than XML, requiring different mindsets to use. I believe that it's not only possible but desirable (if XML is to take off at all) to learn XML without requiring any knowledge at all of its forebears. So you won't find much help here if you're interested primarily in them.
(If you snoop around a bit on the subject of XML, you'll also find copious references to Java and other programming languages. That's largely because XML is still so new that many of its adherents are involved in developing the software that will process XML, and such folks are naturally concerned with language-specific approaches to handling the new markup style. Just XML doesn't have much to say about Java, C++, et al., either.)
So while you're going through this book, put away the wheelbarrows full of knowledge and predispositions you may have acquired about SGML, HTML, and so on. Concentrate on what you want your Web site to say, and on learning how to make it say that, uniquely.
Repeat to yourself: just XML.
SOME THINGS ABOUT ME (AND WHAT THEY IMPLY ABOUT YOU)
First, you need to know that I'm not an SGML guru. In fact, before beginning this book, I knew virtually nothing at all about it. A friend of mine worked in the late 1980s and early 1990s on a project called EDGAR, an SGML application used by the federal Securities & Exchange Commission; I could tell from the bleary-eyed look in this friend's eyes, and implicit in her e-mail messages, that learning or using SGML was not something to be endeavored casually. Beyond that, I knew nothing except very basic principles (such as that HTML was some kind of SGML variant).
I have been a computer applications developer (read "programmer") since 1979. Most of my early work was on mainframe computers, and I graduated thence to UNIX-based minis, and eventually to PCs. My first Internet use was in 1991. I built my first Web page in 1994. My day job is as an applications developer, mostly using Microsoft Access and Visual Basic 5.0, and I'm the Webmaster for my department's Web site; in my spare time I'm also maintaining the site for Anhinga Press, a publisher of poetry, at anhinga.
Why this dreary recitation of a resumé?
No, I'm not fishing for job offers (I'm quite happy where I am). Really, all I want to do is reassure you that, in my opinion, in order to understand and use XML productively:
You don't have to know anything at all about SGML; and
You don't need to know anything at all about HTML, although a general understanding of how it works will help.
In general, I believe that anyone with a basic modicum of intelligence and some simple prior exposure to the Web can use XML. Don't worry about the apparent strangeness of some of its concepts and mechanisms take one step at a time and you'll do just fine.
All right, I confess: There's more to the "why I wrote this book" than all that noble (however sincere) folderol I mentioned at the outset. The fact is, although I work all day with computers and the Internet and think, on the whole, that my life is better because of them there are times when I'm heartily sick of the things. (Not just when they're not working right, either; sometimes I'm so fed up with just sitting in front of them that I'll drop a favorite, entirely smooth-running game before I even have a chance to figure out the first riddle.)
At such times there's nothing I like better than channel surfing for a movie I've never seen. Even better is a trip out to the video-rental store, where I've got some element of control over the selection.
And I'm not talking about recent box-office big hits, either. I mean oddball little films, probably cranked out in black-and-white in the 1940s through 1960s: the ones featuring casts whose names you can't recall fifteen minutes after they've rolled over the screen (while some corny, likewise forgettable score drones or tootles in the background); the ones whose plots revolve around mysterious creatures from other planets, or unlikely chains of criminal circumstance on our own planet, or men in combat fatigues baring their shallow souls to one another while tinny post-production gunfire whizzes and whines overhead. I mean, in short, B movies.
In thinking about B movies, I realized something wonderful about XML: I can think about B movies a lot using XML as a tool for describing them. This would have been nearly impossible to do fully with pure HTML almost certainly requiring me to write a customized, hard-to-maintain program in Perl or some other Web programming language. It'll be a snap (well, almost a snap!) in XML, though.
So throughout this book, be prepared to think not just about XML, but about low-budget cinema (or at least cinema which frequently looks as if it's low-budget) as well.
HOW JUST XML IS ORGANIZED
This book consists of five main parts or sections:
Part 1, XML Basics, will introduce you to everything you need to know about XML itself
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Descrizione libro Prentice Hall Ptr, 1998. Paperback. Condizione libro: New. Codice libro della libreria DADAX0139434178