Both Web 2.0 and Software-as-a-Service (SaaS) almost always depend up on the browser as a common denominator. It is with the web browser that web-based applications are accessed and run, yet the browser model is rapidly reaching its limitations.

Adobe thinks it has the answer and so now does Mozilla.

A year ago, most web developers had to think about Firefox, Internet Explorer, Safari, Opera and perhaps WAP for mobile devices and widget development for one of yet more platforms. Today the horizon is changing and web developers are afforded more opportunity and possibly with that more complexity, through offline development.

Browser extensions now exist that allow for the creation of offline web applications with Dojo Offline, Google Gears, Firefox 3, and other options on the market, pioneering the way and making it possible to take your web application with you on an aeroplane or an underground train.

The drive to make these offline applications desktop applications has also been thrown into the mix, with examples coming from Apple with WebKit Cocoa bindings, Adobe with AIR and Microsoft with Silverlight. Now it is the turn of Mozilla to enter the foray with a project called Prism.

Prism is part of an experiment by Mozilla designed to “bridge the divide in the user experience between web applications and desktop applications“. Essentially, Prism will allow you to create a desktop-like application out of individual websites. These site-specific applications are a growing trend and a trend heavily marketed by, not only Adobe, but now Mozilla, as ‘the future’.

While traditionally users have interacted mostly with desktop applications, more and more of them are using Web applications. But the latter often fit awkwardly into the document-centric interface of Web browsers.

In its current form, Prism doesn’t have the ability to function as a desktop application without access to the Internet, but Mozilla says it is “working to increase the capabilities of those apps by adding functionality to the Web itself, such as providing support for offline data storage and access to 3D graphics hardware.”

Instead of needing to run a browser to, for example, access Google Calendar, a simple icon can be clicked on the desktop. The icon will launch the Google Calendar application inside a Prism window, without any of the additional web browser bloat. This can have its benefits, especially when designing workflows and securing applications as the developer’s pain, the back button and address bar, are removed from the equation.

Although Mozilla may be excited about the concepts behind Prism, and Adobe about AIR not everyone shares the same enthusiasm, or has the working habits that require such an application-based approach. For some, the advantage of web applications is that they inherently aren’t desktop applications and everything can be handled in a single application almost anywhere on the planet, assuming a computer with a browser and web connection. However, Prism, AIR and Silverlight could end up offering the best of both worlds.

Microsoft finally unveiled its new product, Silverlight. But is it actually a product? Not really. It is more aptly described as a runtime system for a cut-down version of the .NET Framework and just-in-time (JIT) compilers. The runtime is tiny, designed to be a plugin to a web browser much like Flash is also available as a plugin. Microsoft see this technology as a potential “Flash killer”, although it is unlikely to achieve such a status, at least in the short to medium term. They have stiff competition from Adobe with the AIR/Flash/Flex combination which is engrained into the designer/developer community.

From the Silverlight website, it is clear that the project is heavily graphics-orientated and can do interesting things with video streams. Somewhat more interesting is that Microsoft have said that it will be consistent across multiple platforms, running on both Windows and Macintosh operating systems. It may even progress to Linux through the partnership with Novell, not to mention support for Windows smartphones and other Windows embedded devices. This is intriguing, yet promising for a company that historically has shunned competing technologies.

Microsoft described Silverlight as “a cross-browser, cross-platform plug-in for delivering the next generation of Microsoft .NET-based media experiences and rich interactive applications for the Web”. The emphasis is on rich interactive applications delivered over the web. The result being applications which offer a new level of user interactivity to rival that of the desktop and firmly banish HTML-based website to the bin. Sounds familiar? Flash?

So how is it different from AIR/Flash/Flex? Essentially, you can use any of the languages supported under the .NET framework, which means that Silverlight applications can be written in C# or Visual Basic, as well as other languages such as Ruby and Python. Like the AIR/Flash/Flex combination, Silverlight has its own set of development and debug tools in Visual Studio and a complete Expression suite for visual designers.

The Killer Application?

Silverlight on its own will not be the killer application so-to-speak. It is the services behind Silverlight, the data streaming services, that will be a key differentiator. Combining Silverlight with Microsoft’s new initiative, quietly referred to as “Live 2.0″, will provide video storage and streaming capabilities worthy of a Google-styled offering. These streaming services will clearly carry some form of advertising. You don’t have to use the Microsoft service, but the intention is clear; high-bandwidth, high-availability streaming of video data requires huge investment and Microsoft is making that investment to take its own slice of a huge, fledgling market.

Video streaming isn’t the only part of the service. Microsoft plans to develop facilities such as server-side data and credit card processing. This opens up possibilites for an application developed in Silverlight to be hosted, managed and distributed by Microsoft or another partner. I hear alarm bells … hosted, managed and distributed all by Microsoft! This is clearly putting all your eggs in one basket, but prudence is key when choosing which services to sign up to.

The Future Is Online.

With Silverlight, Microsoft has shifted its emphasis and signalled a firm intention that the future is online. It will be offering end-to-end solutions that allow the design and development of systems, and the management and distribution of those systems based around web services running not only locally but out in the etha of the Internet. Utimately we will be able to choose when, where and how we access applications and information. Whether Microsoft’s vision can be successful is dependent on whether this behemoth of a company can metamorphose from a conservative institution into a dynamic one. They have the money, the intellect and the technology, they now need the spirit of a precocious of a teenager.