Threading Objects and Features
.NET Framework 4.5
The .NET Framework provides a number of objects that help you create and manage multithreaded applications. Managed threads are represented by the Thread class. The ThreadPool class provides easy creation and management of multithreaded background tasks. The BackgroundWorker class does the same for tasks that interact with the user interface. The Timer class executes background tasks at timed intervals.
In addition, there are a number of classes that synchronize activities of threads, including the Semaphore and EventWaitHandle classes introduced in the .NET Framework version 2.0. The features of these classes are compared in Overview of Synchronization Primitives.