So GM is turning to eXtensible Markup Language (XML) to Web-enable its huge mass of legacy system data. XML, like its cousin HTML (HyperText Markup Language), is a language for presenting documents on the Web. But XML's capabilities extend far beyond those of HTML (see sidebar below, "What is XML?"). The primary advantage over HTML is that XML is extensible--users can define their own electronic document types, making it easier to exchange data not only within an organization but also among different companies. Experimenting with XML General Motors is looking to XML not only to allow it to put data from its legacy systems into Web format but also to make that data more accessible in the future. "We're trying to create an environment where applications can be built very quickly and be extended to wherever we need them much faster than we've been able to do it in the past," says Walsh. "We want to be able to build systems in such a way that they are no longer an impediment moving forward." GM is experimenting with XML pilot projects in areas such as quality assurance, electronic commerce, and finance, among others. In one project, the automaker is using XML technology from DataChannel Inc. and visualization software from Engineering Animation Inc. to pull engineering information from various legacy systems to present three-dimensional images--of a car or truck axle, an exhaust system, or even a complete vehicle--in a Web browser. Along with the CAD/CAM images, GM engineers can see when the drawing was last updated and which engineers worked on it. The problem: How to make GM's huge mass of legacy data accessible from new applications running on Web browsers. The solution: XML lets GM use data from its legacy systems in new applications that employees can access using standard Web browsers. GM is counting on XML's flexibility to allow it to use this data in new applications in the future, regardless of what the user interface looks like. The IT infrastructure: GM has a massive IT infrastructure, including 136,000 PCs and some 8,500 different applications. GM's data stores hold more than 110 terabytes of data, much of it in VSAM, DB2, and other legacy systems. GM has no way of predicting what tools users will employ in the future to get information, Walsh says. The user interface might, for example, be a device like a PalmPilot or a telephone. If it can't make a bridge between its existing data and new ways of using the information, any application the company builds is "still going to be a legacy system," he says. And XML, says Walsh, does "a very good job" of bridging the gap between the Web and IMS, DB2, and other legacy applications.
How do you move 110 terabytes of data onto the Web? That's the challenge facing General Motors Corp. as it tries to bring its enormous investment in existing IT systems into the age of the Internet. GM--the world's largest corporation--has more than 8,500 applications, many of them running on mainframes. With Web browsers rapidly becoming the user interface of choice, the company simply can't afford to leave all that data behind. But no one, says Dennis Walsh, executive director of advanced technologies for the Onstar Division of GM, "can afford to rewrite that many systems."
A relatively new standard, XML was adopted by the W3C (World Wide Web Consortium, http://www.w3c.org) in Feb. 1998. A growing number of companies are building XML applications, but XML is still in "the early adopter stage," says Michael Goulde, an executive vice president at the Patricia Seybold Group in Boston. Few, however, argue that XML is going to play a very important role in computing over the next few years. 
GM's Dennis Walsh: XML is the solution for Web - enabling a huge mass of legacy data.
XML is being welcomed so enthusiastically, Goulde says, because it's seen "as a way to solve a whole series of problems. Between now and the end of this year we're going to see people using XML as a way to integrate multiple data sources, to communicate with business partners, to build extranets, and to make information available over the Web."
The Business Community Increasingly Embraces XML
In 1998, IT professionals started adopting XML. Its usage exploded within months.

The company is also building XML into its Onstar system. Onstar, introduced in GM's Cadillac line several years ago and now offered with many vehicles, lets GM customers use a cellular phone and Global Positioning System to communicate with company operators who can provide directions and assistance. GM plans to use XML to enable the vehicle to communicate on its own, allowing it, for instance, to alert the company if there is a crash and a disabled driver is unable to call for help.
AT A GLANCE: General Motors Corp.
The company: The world's largest corporation, the Flint, Mich.-based automaker has 647,000 employees and revenues last year of more than $161 billion.