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Click Here to see a
80KB bitmap image of artwork
which goes with this article, entitled:
ActiveX: Well Integrated
Making a client/server pair from a browser and a server is an easy proposition--in theory. However, browsers are politely called "thin clients" because they don't incorporate much intelligence. Most work done on the Web is concentrated on the server side, which further slows the already-overburdened Internet. Considering the power of the average PC today, that's a real waste of CPU performance.
Both Netscape and Microsoft recognize this problem. Each of their browsers includes enhancements that let the client carry more weight.
One way to get the browser working a little harder is to include executable scripting language directly in an HTML page. Netscape was the first to incorporate JavaScript, a language it designed with Sun Microsystems, into its browser. Microsoft Internet Explorer 3.0 now also supports JavaScript as well as Microsoft's own VBScript language.
These two scripting languages are functionally equivalent. The difference lies mostly in preferences: The C-like syntax of JavaScript will appeal to some, while others will want the ease of the Visual Basic-influenced VBScript. Since JavaScript is supported by both browsers, it's likely to be the dominant scripting language.
Think of JavaScript and VBScript as batch file languages for the Web. Although scripting languages can do simple tasks, they fall short of the programming power needed to run a full-fledged application in a browser window. That's where Java and ActiveX technologies come in.
Java is a programming language designed by Sun. It was adopted by Netscape in Navigator 2.0 and Microsoft in Internet Explorer 3.0. Java apps are interpreted by the browser. They are hardware-independent, running on a Windows PC, Macintosh or a variety of UNIX systems.
The interpreter can enforce security restrictions that wouldn't be possible if Java were a system-specific app. However, there have been more than a half-dozen well-publicized failures of Java's security since Navigator 2.0 was first released.
Microsoft is advocating ActiveX technology as a way to develop Web-based applications. ActiveX is essentially a renamed version of OLE 2.0, with extensions to accommodate the low-bandwidth connections typical of the Internet.
There are a few drawbacks here as well. ActiveX is currently available only for Windows platforms. In addition, it doesn't have the security restrictions of Java--an ActiveX application can do anything it pleases on your system. Performance is a plus because ActiveX isn't an interpreted language like Java. As a result, it runs much faster.
"Thickening" your browser to a meatier form with scripting languages is a great way to use the Web for more than just static information--but the choice of which language to use will depend on your needs, your programming skill and the platforms you wish your site to reach.
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