SGML: What's so big about XML?

SGML: What's so big about XML?

Subject: Re: What's so big about XML?
Date: Tue, 28 Jan 1997 14:43:21 -0600
From: Len Bullard <cbullard@hiwaay.net>
Newsgroup: comp.text.sgml
------------------------------------------------ kendall shaw wrote: > > Hi, > > I've been reading about XML a little, and I understand it's syntax > pretty much. What I don't know about is how it will be used. What > about XML would be easier to present over the web than SGML? Or, > what about presenting SGML on the web is so hard that we would need > XML? How will presentation of XML element structure be done >(stylesheets)? An overview, not authoritative, but not uninformed: SGML has many features that require a parser to be quite complex. Some of these features support requirements that either don't apply to hypermedia, or don't occur often enough to concern all applications. SGML CAN be used on the web and is everyday in the form of an SGML application called HTML. To understand a difference, consider how many times we have seen the phrase "... HTML, a subset of SGML" and had to remind the writer that HTML is NOT a subset of SGML, it is an application. However, XML IS a proper subset of SGML. It is designed such that a parser can be *easily* written for any application that wishes to use its syntax. Furthermore, as we speak, a subset of other hypermedia link and location specifications (ie., HyTime and TEI) is being written so that hyperlinking among XML applications will be portable and interoperable. That alone is worth the price of admission. But there's more! In the next phase, the stylesheet/processing specification component will be written such that XML applications can exchange information with assurance of rendering and behavior fidelity. This is a fantastic contribution to a community that has needed this for a decade now. In short, XML will provide an integrated suite of specifications which an application developer can in part, or in total, use to create applications for the Internet and World Wide Web which are compatible with current systems, and which take advantage of the power of generalized markup. Note carefully: XML does not replace SGML or HTML. In the former, XML is a subset so brings, as originally intended, SGML to the Web. In the latter, XML applications will work with and augment HTML applications by making it possible to use languages such as the Chemical Markup Language (CML) as effectively as one now uses HTML. Browsers and plugins can be written for very specific information domains that still interoperate in the generalized environment of the WWW and Internet. One market for this will be moving the gigabytes of SGML out there, originally designed for print applications or say, military technical manuals onto the Internet and into intranets. The XML Working Group is *furiously* moving on its tasks. I expect by spring to see some prototypes emerging from the members. I expect by fall to see real applications. Just a prediction. Len Bullard Lockheed Martin Subject: Re: What's so big about XML?
Date: Wed, 29 Jan 1997 14:16:20 -0600
From: Len Bullard <cbullard@hiwaay.net>
Newsgroup: comp.text.sgml
-------------------------------------------------------------- Paul Hayslett wrote: > > Hmmmm..... I would have said something along the lines of: [snip] > "The best part is that we now get to watch as vendors who, until recently, > were charging 10's of 1000's of dollars per license for SGML-aware products > try to educate us on the need for moderately priced systems which handle > only the subset of SGML that users are likely to use. As if we hadn't been > asking for exactly that for 10 years." > > But maybe I'm just a cynic. I can't quarrel with your assessment. That is why IADS is out there for free. People took significant risks to make that possible, and paid a price. I am one of them. But, water under the bridge. The significance of XML is that the vendors, academicians, SGML designers, hypertext experts and yes, some significant players from the HTML community have sat down under the aegis of the W3C to create XML. That's amazing. Now, what would be most interesting would be a discussion of the kind of products that can be created with XML. Using a similar design, we built IADS and gave it away. Neat little browser, a bit long in the tooth now, but it proved a lot about the use of simplification of SGML and the use of an automated stylesheet system. That's one model. Another and probably more interesting model is Peter Murray-Rust's CML language and application. A lot can be done with a GUI tree object. Wouldn't it be a good thread to talk about applying XML and what an XML product would look like, feel like, and do? How simple can we make an XML application? How easy can we make it to use? What do you want it to do and how do you want to do that? The SGML community has been scarred for years with relentless infighting and scorn. The marvel of XML is that it IS happening and who is there doing it. As a decade long denizen, I am not just a little thrilled that this is happening regardless of cause or circumstance. It is important, I think, to now ask ourselves what we shall do with this toy. What will it be like to have something a bit more powerful than HTML, a little bit harder to use, but with a lot more possibilities for domain-specific data handlers that interoperate and can share linking and stylesheet definitions? A real opportunity is opening up for the first time in a decade. What shall we make of it? Len Bullard Lockheed Martin