Microsoft Silverlight is a cross-browser, cross-platform plug-in for delivering the next generation of media experiences and rich interactive applications. It helps enrich your websites and make them more interactive and engaging.
What's New in Silverlight 3 topic introduces some of the new features in Silverlight 3. Silverlight 3 applications are no longer restricted to running in a browser. They can be run in a browser or it they can be detached from the browser and run from the desktop. These out-of-browser applications allow you to bring the richness of Silverlight 3 applications directly to the desktop without the restriction of running within a browser. Check Building An Out-of-Browser Client With Silverlight 3 article by John Papa.
The developer documentation for Silverlight 3 can be downloaded here - Microsoft Silverlight 3 Offline Documentation
How to Start?
You can start learning Silverlight by using resources given below:
There is tons of material available on Microsoft websites given above. Given below are some resources I would recommend:
Walkthrough: Creating Your First Silverlight Application - This walkthrough shows you how to get started programming in Silverlight and Visual Studio by creating a simple application
Walkthrough: Creating a Silverlight Clock by Using Expression Blend or Code - This walkthrough steps you through the creation of a simple clock using Microsoft Silverlight
Scott Guthrie's 8-part blog series - Scott's blog posts will walk you through the fundamentals of Silverlight and will help you build a sample application along the way
The Silverlight SDK Sample Browser provides access to all of the live samples used by the Silverlight documentation.
Videos – Frankly, too many of them are available :-) So, browse links below and then pick and choose the videos which you find relevant.
Development Tools Needed
Silverlight in SharePoint 2007
Silverlight does not work out-of-the-box in SharePoint 2007. Please refer to How to configure your SharePoint extended IIS Web App for working with Silverlight 2 applications post on Patrick Tisseghem's Blog for changes required in web.config file for the SharePoint IIS Web application.
Read the RIA: Light Up SharePoint With Silverlight 2 Web Parts by Steve Fox and Paul Stubbs to learn one of the way in which in Silverlight Web parts can be created for use in a SharePoint site.
You can try the MSDN Virtual Lab: Rich Internet Applications with Silverlight and SharePoint - C# to become familiar with:
Karine Bosch's blog has some useful posts on Silverlight and SharePoint:
Silverlight Blueprint for SharePoint
The Silverlight Blueprint for SharePoint is source code and guidance for developers describing how to use Microsoft Silverlight and Microsoft SharePoint Products and Technologies together in business applications and Internet Web sites. Following samples are included in the kit to get you started:
Useful CodePlex projects
Silverlight Toolkit: Collection of Silverlight controls, components and utilities made available outside the normal Silverlight release cycle
SmartTools.Charts: Shows Silverlight charts based on data stored in SharePoint lists or document libraries
SilverPart 2.0: a Silverlight wrapper Web Part that can be used in MOSS 2007 or WSS 3.0 to expose Silverlight 2 content
Professional SharePoint 2007 Development using Silverlight 2 by Paul Stubbs and Steve Fox.
Using Silverlight in SharePoint Online
You can also use Silverlight in SharePoint Online. Refer to Using Silverlight with SharePoint Online from Microsoft Online Services post in Microsoft Online Services Team Blog. In this post, Troy Hopwood, Program Manager II on the Microsoft Online Services Engineering team, walks through creating a basic Silverlight control that integrates with SharePoint Online via Web Services that can then be deployed to SharePoint Online.
Great post. Lots of resources. Thank you very much for the post.