What Is Silverlight And Do I Need It?

Do You Need Silverlight?

You've probably seen the message: "An application you want to download may require Silverlight." May? If that's marketing, I'm not convinced that I need the product. So what exactly is Silverlight?

Fundamentally, Silverlight is Microsoft's competitive answer to Adobe's Flash, the long-standing dominant standard for multimedia Web applications. Silverlight integrates animations, video, and interactivity (the ability to click on an animated item and trigger a response). Web site developers can do things that would be difficult or impossible without Silverlight. But does that mean they should?

Silverlight requires Microsoft's .NET Framework, another optional Windows component. .NET is probably going to become the prevailing standard under which new Windows applications are developed, so eventually you will need to install it. But is Silverlight going to become a multimedia standard so widely used by Web sites that you absolutely positively must have it in order to enjoy Web surfing adequately?

Probably not, because Silverlight is not compatible with Linux. And most Web servers are running some flavor of Linux. Novell has released Moonlight, a Linux-based free software implementation of Silverlight's framework, in conjunction with Microsoft. But it does not have the full functionality of Silverlight and will probably lag behind for years to come.

Is Silverlight Compatible With My System?

Compatibility with Web browsers is also important for any Web server's software framework. Silverlight is compatible with Firefox, SeaMonkey, Safari, Opera, and Google Chrome - but not under all operating systems. Of course, Silverlight is compatible with Microsoft's own Internet Explorer v6 and later. To see which operating systems support Silverlight under which browsers, see this Wikipedia table.

Adobe Air and Flash are other reasons Silverlight probably won't dominate the Web. Adobe Air is analogous to Microsoft .NET Framework; both provide vast libraries of functions that save programers lots of time and support standardized ways of doing things in applications. Flash/Air competes directly with Silverlight/.NET. Adobe Flash is already the standard multimedia platform on the Web, so the Adobe platform has quite an edge in competition. To learn more about programming Silverlight applications, visit the official Silverlight site.

Who is using Silverlight? eBay, for one. "When you really need to know if you won that eBay item," says Microsoft developer and Silverlight community leader, "use the new auction item tracker tool created by eBay using Silverlight and Internet Explorer 8 (IE 8). This tool allows you to easily track all the items you are interested in as well as see which auctions you've won with a drag and drop tool that runs as a side bar to eBay in IE 8."

Yes, you need IE 8 to use eBay's Silverlight tool. That's a problem with software frameworks such as Silverlight. A Web developer may not have the resources to design the same app for all operating system/browser combinations. We end up with a fragmented Web. People must switch browsers; download and install multiple platforms (.NET, Adobe Air); and add several browser plugins that do the same thing only differently. But that's the free market for you. And we do like the free market.

Resistance May Not Be Futile

So far, I've resisted the siren call of Silverlight on my office computer, and I don't feel like I'm missing anything. Probably because right now, there really aren't many sites using Silverlight. My advice on Silverlight, as with all new software platforms, is to wait until it reaches out and pulls you in. (Remember VRML?) Don't install Silverlight just because Microsoft recommends it. Wait until some new software or ultra-cool website that requires Silverlight comes along, and you just gotta have it.

Got something to say about Silverlight? Post your comments or questions below...