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.NET is a software framework supporting a multi-language paradigm and supporting language interoperability. .NET applications are executed in a virtual machine (CLR) which provides a few important services: security, memory management and exception handling.

The .NET Framework is not specific to any one programming language. The , , , and programming languages from Microsoft, as well as many other languages from other vendors, all use the same .

The .NET Framework includes a large of as part of the Base Class Library (BCL), including those related to user interface design, data access, database connectivity, , development of web applications, mathematical algorithms, and network communications. This extensive library simplifies development and makes it easy to rapidly develop new applications.

Getting help

Versions of .NET

Stable release

  • .Net Framework 4.8 / 10 May 2019;
  • .NET Core 2.2 / 12 Apr 2018;

Garbage collector

Free .NET Programming Books (C# / F# / VB / Nemerle / Visual Studio)

Useful .NET Libraries


  • Math.NET Numerics - special functions, linear algebra, probability models, random numbers, interpolation, integral transforms, and more.

Package managers for external libraries

  • NuGet (formerly known as NuPack) - Microsoft (developer-focused package management system for the .NET platform intent on simplifying the process of incorporating third-party libraries into a .NET application during development).
  • OpenWrap - Sebastien Lambla - Open Source Dependency Manager for .NET applications.

Build Tools

  • Prebuild - Generate project files for all Visual Studio versions, including major IDEs and tools like SharpDevelop, MonoDevelop, NAnt, and Autotools.

Dependency Injection/Inversion of Control



Design by Contract



Data Mapper



PDF Creators/Generators

Unit Testing/Mocking

Automated Web Testing

Misc Testing/Quality Support/Behavior Driven Development (BDD)

URL Rewriting

Web Debugging

  • Glimpse - Firebug for your webserver


MS Word/Excel Documents Manipulation

  • DocX to create, read, and manipulate formatted word documents. Easy syntax, working nicely, actively developed. No Microsoft Office necessary.
  • Excel XML Writer allows creation of .XLS (Excel) files. No Microsoft Office necessary. It has been a while since it has been updated. It also provides a code generator to create code from already created XLS file (saved as XML).
  • Excel Reader allows creation/reading of .XLS (Excel) files. No Microsoft Office necessary. It has been a while since it has been updated.
  • Excel Package allows creation/reading of .XLSX (Excel 2007) files. No Microsoft Office necessary. The author is gone, so it is out of date.
  • EPPlus is based on Excel Package and allows creation and reading of .XLSX (Excel 2007). It is actually the most advanced even comparing to NPOI.
  • NPOI is the .NET version of POI Java project at POI is an open source project which can help you read/write Excel, Word, and PowerPoint files. Latest sources available at GitHub repository.

Social Media

  • LINQ to Twitter - LINQ-based wrapper for all Twitter API functionality in C#.
  • Facebook C# SDK - A toolkit for creating Facebook applications / integrating websites with Facebook using the new Graph API or the old rest API.


  • sharpSerializer - XML/binary serializer for WPF, ASP.NET AND Silverlight.
  • protobuf-net - .NET implementation of Google's cross-platform binary serializer (for all .NET platforms).

Machine learning

  • Encog C# - Neural networks
  • - AI, computer vision, genetic algorithms, machine learning

RESTFul Web Services

  • RestSharp - Simple REST and HTTP API Client for .NET