This document summarizes the history and features of Microsoft's .NET Framework. It discusses the major releases from .NET 1.0 in 2002 through the current .NET 4.0. For each release, it highlights new capabilities like Windows Forms, ASP.NET, WPF, WCF, and LINQ. It also summarizes new areas in .NET 4.0 like parallel computing, the dynamic language runtime, and improvements to ADO.NET, Entity Framework, and Windows Workflow Foundation.