The .NET Framework 3.5 Service Pack 1 (SP1) delivers more controls, improved start-up performance, AJAX support, and powerful new graphics features for client development. Visit the .NET Framework downloads page for more information.
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Windows Presentation Foundation (WPF)Use WPF for building applications and high fidelity experiences in Windows Vista.
Windows Communication Foundation (WCF)Use WCF for building and running connected systems.
Windows Workflow Foundation (WF)Use WF for building workflow-enabled applications on Windows.
Windows FormsUse Windows Forms for building smart client applications.
Base Class Libraries (BCL)The BCL provides the fundamental building blocks for any application.
.NET ServicesUse .NET Services to connect cloud-based and cloud-aware applications.
ASP.NETASP.NET is a free technology for building dynamic web applications.
ADO.NETUse ADO.NET to access data sources such as Microsoft SQL Server, OLE DB, and XML.
Common Language Runtime (CLR) The CLR is the .NET Framework run-time environment.
Windows CardSpaceWindows CardSpace provides the consistent user experience required by the identity metasystem.
.NET Compact FrameworkUse .NET Compact Framework to build applications for Windows CE-based devices.
.NET Micro FrameworkUse the .NET Micro Framework to develop for resource-constrained devices.
Important updates and highlights of .NET Framework content in the MSDN Library.
More .NET Framework Library Content...
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