This article contains a list of

libraries A library is a collection of materials, books or media that are accessible for use and not just for display purposes. A library provides physical (hard copies) or digital access (soft copies) materials, and may be a physical location or a vir ...

that can be used in

.NET languages CLI languages are computer programming languages that are used to produce libraries and programs that conform to the Common Language Infrastructure (CLI) specifications. With some notable exceptions, most CLI languages compile entirely to the Com ...

. These languages require

.NET Framework The .NET Framework (pronounced as "''dot net"'') is a proprietary software framework developed by Microsoft that runs primarily on Microsoft Windows. It was the predominant implementation of the Common Language Infrastructure (CLI) until bein ...

, Mono, or .NET, which provide a basis for

software development Software development is the process of conceiving, specifying, designing, programming, documenting, testing, and bug fixing involved in creating and maintaining applications, frameworks, or other software components. Software development invol ...

, platform independence, language interoperability and extensive framework libraries. Standard Libraries (including the

Base Class Library The Standard Libraries is a set of libraries included in the Common Language Infrastructure (CLI) in order to encapsulate many common functions, such as file reading and writing, XML document manipulation, exception handling, application global ...

) are not included in this article.

Preamble

Apps created with .NET Framework or .NET run in a software environment known as the Common Language Runtime (CLR), an

application virtual machine In computing, a virtual machine (VM) is the virtualization/emulation of a computer system. Virtual machines are based on computer architectures and provide functionality of a physical computer. Their implementations may involve specialized hard ...

that provides services such as security,

memory management Memory management is a form of resource management applied to computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse whe ...

, and

exception handling In computing and computer programming, exception handling is the process of responding to the occurrence of ''exceptions'' – anomalous or exceptional conditions requiring special processing – during the execution of a program. In general, a ...

. The framework includes a large class library called

Framework Class Library The Framework Class Library (FCL) is a component of Microsoft's .NET Framework, the first implementation of the Common Language Infrastructure (CLI). In much the same way as Common Language Runtime (CLR) implements the CLI Virtual Execution Sys ...

(FCL). Thanks to the hosting virtual machine, different .NET CLI-compliant languages can operate on the same kind of data structures. Therefore, all CLI-compliant languages can use FCL and other .NET libraries that are written in one of the CLI compliant languages. When the source code of a CLI-compliant language is compiled, the compiler generates platform-independent code in the

Common Intermediate Language Common Intermediate Language (CIL), formerly called Microsoft Intermediate Language (MSIL) or Intermediate Language (IL), is the intermediate language binary instruction set defined within the Common Language Infrastructure (CLI) specification. ...

(CIL, also referred to as

bytecode Bytecode (also called portable code or p-code) is a form of instruction set designed for efficient execution by a software interpreter. Unlike human-readable source code, bytecodes are compact numeric codes, constants, and references (normall ...

), which is stored in CLI assemblies. When a .NET app runs, the

just-in-time compiler In computing, just-in-time (JIT) compilation (also dynamic translation or run-time compilations) is a way of executing computer code that involves compilation during execution of a program (at run time) rather than before execution. This may c ...

(JIT) turns the CIL code into platform-specific machine code. To improve performance, .NET Framework also comes with the

Native Image Generator The Native Image Generator, or simply NGen, is the ahead-of-time compilation (AOT) service of the .NET Framework. It allows a CLI assembly to be pre-compiled instead of letting the Common Language Runtime (CLR) do a just-in-time compilation (JI ...

(NGEN), which performs ahead-of-time compilation to machine code. This architecture provides

language interoperability Language interoperability is the capability of two different programming languages to natively interact as part of the same system and operate on the same kind of data structures. There are many ways programming languages are interoperable with on ...

. Each language can use code written in other languages. Calls from one language to another are exactly the same as would be within a single programming language. If a library is written in one CLI language, it can be used in other CLI languages. Moreover, apps that consist only of pure .NET assemblies, can be transferred to any platform that contains an implementation of CLI and run on that platform. For example, apps written using .NET can run on Windows,

macOS macOS (; previously OS X and originally Mac OS X) is a Unix operating system developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac computers. Within the market of desktop and lap ...

, and various versions of

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which in ...

. .NET apps or their libraries, however, may depend on native platform features, e.g.

COM Com or COM may refer to: Computing * COM (hardware interface), a serial port interface on IBM PC-compatible computers * COM file, or .com file, short for "command", a file extension for an executable file in MS-DOS * .com, an Internet top-level d ...

. As such, platform independence of .NET apps depends on the ability to transfer necessary native libraries to target platforms. In 2019, the

Windows Forms Windows Forms (WinForms) is a free and open-source graphical (GUI) class library included as a part of Microsoft .NET, .NET Framework or Mono Framework, providing a platform to write client applications for desktop, laptop, and tablet PCs. While ...

and

Windows Presentation Foundation Windows Presentation Foundation (WPF) is a free and open-source graphical subsystem (similar to WinForms) originally developed by Microsoft for rendering user interfaces in Windows-based applications. WPF, previously known as "Avalon", was initia ...

portions of .NET Framework were made open source.

.NET implementations

There are four primary .NET implementations that are actively developed and maintained: *

: The original .NET implementation that has existed since 2002. While not yet discontinued, Microsoft does not plan on releasing its next major version, 5.0. * Mono: A cross-platform implementation of .NET Framework by

Ximian Ximian, Inc. (previously called Helix Code and originally named International Gnome Support) was an American company that developed, sold and supported application software for Linux and Unix based on the GNOME platform. It was founded by Miguel ...

, introduced in 2004. It is free and open-source. It is now developed by

Xamarin Xamarin is a Microsoft-owned San Francisco-based software company founded in May 2011 by the engineers that created Mono, Xamarin.Android (formerly Mono for Android) and Xamarin.iOS (formerly MonoTouch), which are cross-platform implementatio ...

, a subsidiary of Microsoft. *

Universal Windows Platform Universal Windows Platform (UWP) is a computing platform created by Microsoft and first introduced in Windows 10. The purpose of this platform is to help develop universal apps that run on Windows 10, Windows 10 Mobile (discontinued), Windows 1 ...

(UWP): An implementation of .NET used for building

UWP apps Universal Windows Platform (UWP) apps (formerly Windows Store apps and Metro-style apps) are applications that can be used across all compatible Microsoft Windows devices, including personal computers (PCs), tablets, smartphones, Xbox One, Mic ...

. It's designed to unify development for different targeted types of devices, including PCs, tablets, phablets, phones, and the

Xbox Xbox is a video gaming brand created and owned by Microsoft. The brand consists of five video game consoles, as well as applications (games), streaming services, an online service by the name of Xbox network, and the development arm by the na ...

. * .NET: A cross-platform re-implementation of .NET Framework, introduced in 2016 and initially called ''.NET Core''. It is

free and open-source Free and open-source software (FOSS) is a term used to refer to groups of software consisting of both free software and open-source software where anyone is freely licensed to use, copy, study, and change the software in any way, and the source ...

. .NET superseded .NET Framework with the release of .NET 5. Each implementation of .NET includes the following components: * One or more runtime environments, e.g. CLR for .NET Framework and

CoreCLR The domain name net is a generic top-level domain (gTLD) used in the Domain Name System of the Internet. The name is derived from the word ''network'', indicating it was originally intended for organizations involved in networking technologies ...

for .NET * A class library The .NET Standard is a set of common APIs that are implemented in the

of any .NET implementation. The class library of each implementation must implement the .NET Standard, but may also implement additional APIs. Traditionally, .NET apps targeted a certain version of a .NET implementation, e.g. .NET Framework 4.6. Starting with the .NET Standard, an app can target a version of the .NET Standard and then it could be used (without recompiling) by any implementation that supports that level of the standard. This enables portability across different .NET implementations. The following table lists the .NET implementations that adhere to the .NET Standard and the version number at which each implementation became compliant with a given version of .NET Standard. For example, according to this table, .NET Core 3.0 was the first version of .NET Core that adhered to .NET Standard 2.1. This means that any version of .NET Core bigger than 3.0 (e.g. .NET Core 3.1) also adheres to .NET Standard 2.1.

Web frameworks

;

ASP.NET ASP.NET is an open-source, server-side web-application framework designed for web development to produce dynamic web pages. It was developed by Microsoft to allow programmers to build dynamic web sites, applications and services. The name sta ...

: a server-side web application framework designed for web development to produce dynamic web pages. It is the successor to Microsoft's Active Server Pages (ASP) technology built on the Common Language Runtime (CLR). It provides separate patterns for developing web applications ASP.NET MVC, ASP.NET Web API, and ASP.NET Web Pages (a platform using only

Razor A razor is a bladed tool primarily used in the removal of body hair through the act of shaving. Kinds of razors include straight razors, safety razors, disposable razors, and electric razors. While the razor has been in existence since before t ...

pages), which have merged into a unified MVC 6. ;

ASP.NET Core ASP.NET Core is a free and open-source web framework and successor to ASP.NET, developed by Microsoft. It is a modular framework that runs on both the full .NET Framework, on Windows, and the cross-platform .NET. However, ASP.NET Core version 3 ...

: a successor and re-implementation of ASP.NET as a modular web framework, together with other frameworks like Entity Framework. The framework uses the new open-source .NET Compiler Platform (codename "Roslyn") and is cross platform. ;

Blazor Blazor is a free and open-source web framework that enables developers to create web apps using C# and HTML. It is being developed by Microsoft. Overview Five different editions of Blazor apps have been announced. Blazor Server: These apps ar ...

: a

web framework A web framework (WF) or web application framework (WAF) is a software framework that is designed to support the development of web applications including web services, web resources, and web APIs. Web frameworks provide a standard way to build and ...

that enables developers to create Web apps using C# and

HTML The HyperText Markup Language or HTML is the standard markup language for documents designed to be displayed in a web browser. It can be assisted by technologies such as Cascading Style Sheets (CSS) and scripting languages such as JavaScript ...

. Blazor Server apps are hosted on an

server in

ASP.NET Razor Razor is an ASP.NET programming syntax used to create dynamic web pages with the C# or VB.NET programming languages. Razor was in development in June 2010 and was released for Microsoft Visual Studio 2010 in January 2011. Razor is a simple-synt ...

format, while Blazor WebAssembly apps are Single-page apps that are downloaded to the client's web browser before running.

Numerical libraries

Open-source numerical libraries

; AForge.NET: a computer vision and artificial intelligence library. It implements a number of genetic, fuzzy logic and machine learning algorithms with several architectures of artificial neural networks with corresponding training algorithms. ;

ALGLIB ALGLIB is a cross-platform open source numerical analysis and data processing library. It can be used from several programming languages ( C++, C#, VB.NET, Python, Delphi). ALGLIB started in 1999 and has a long history of steady development with ...

: a cross-platform open source numerical analysis and data processing library. It consists of algorithm collections written in different programming languages (C++, C#, FreePascal, Delphi, VBA) and has dual licensing – commercial and

GPL The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software. The license was the first copyleft for general us ...

. ; Math.NET Numerics: aims to provide methods and algorithms for numerical computations in science, engineering and every day use. Covered topics include special functions, linear algebra, probability models, random numbers, interpolation, integral transforms and more. MIT/X11 license. ; Meta.Numerics: is a library for advanced scientific computation in the .NET Framework.

Proprietary numerical libraries

; ILNumerics.Net: a commercial high performance, typesafe numerical array classes and functions for general math, FFT and linear algebra, aims .NET/mono, 32&64 bit, script-like syntax in C#, 2D & 3D plot controls, efficient memory management. Released under GPLv3 or commercial license. ; Measurement Studio: a commercial integrated suite UI controls and class libraries for use in developing test and measurement applications. The analysis class libraries provide various digital signal processing, signal filtering, signal generation, peak detection, and other general mathematical functionality. ;

NMath NMath is a numerical package for the Microsoft .NET Framework. It is developed by CenterSpace Software. Version 1.0 was released in March, 2003 as NMath Core. The current version is called NMath 7.1, released in December, 2019. NMath is built on ...

: Commercial numerical component libraries for the .NET platform by CenterSpace Software, including signal processing (FFT) classes, a linear algebra (LAPACK & BLAS) framework, and a statistics package.

3D graphics

Open-source 3D graphics

; Open Toolkit (OpenTK): a low-level C# binding for

OpenGL OpenGL (Open Graphics Library) is a cross-language, cross-platform application programming interface (API) for rendering 2D and 3D vector graphics. The API is typically used to interact with a graphics processing unit (GPU), to achieve hardwa ...

OpenGL ES OpenGL for Embedded Systems (OpenGL ES or GLES) is a subset of the OpenGL computer graphics rendering application programming interface (API) for rendering 2D and 3D computer graphics such as those used by video games, typically hardware-accel ...

and

OpenAL OpenAL (Open Audio Library) is a cross-platform audio application programming interface (API). It is designed for efficient rendering of multichannel three-dimensional positional audio. Its API style and conventions deliberately resemble those ...

. It runs on Windows, Linux, Mac OS X, BSD, Android and iOS. It can be used standalone or integrated into a GUI. ;

(WPF): a graphical subsystem for rendering user interfaces, developed by Microsoft. It also contains a 3D rendering engine. In addition, interactive 2D content can be overlaid on 3D surfaces natively. It only runs on Windows operating systems.

Proprietary 3D graphics

;

Unity Unity may refer to: Buildings * Unity Building, Oregon, Illinois, US; a historic building * Unity Building (Chicago), Illinois, US; a skyscraper * Unity Buildings, Liverpool, UK; two buildings in England * Unity Chapel, Wyoming, Wisconsin, US; ...

: a cross-platform

game engine A game engine is a software framework primarily designed for the development of video games and generally includes relevant libraries and support programs. The "engine" terminology is similar to the term "software engine" used in the software in ...

developed by Unity Technologies and used to develop

video game Video games, also known as computer games, are electronic games that involves interaction with a user interface or input device such as a joystick, controller, keyboard, or motion sensing device to generate visual feedback. This feedback m ...

s for PC, consoles,

mobile device A mobile device (or handheld computer) is a computer small enough to hold and operate in the hand. Mobile devices typically have a flat LCD or OLED screen, a touchscreen interface, and digital or physical buttons. They may also have a physical k ...

s and

website A website (also written as a web site) is a collection of web pages and related content that is identified by a common domain name and published on at least one web server. Examples of notable websites are Google, Facebook, Amazon, and Wikipe ...

Image processing

; AForge.NET: a computer vision and artificial intelligence library. It implements a number of image processing algorithms and filters. It is released under the

LGPLv3 The GNU Lesser General Public License (LGPL) is a free-software license published by the Free Software Foundation (FSF). The license allows developers and companies to use and integrate a software component released under the LGPL into their own ...

and partly

GPLv3 The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the four freedoms to run, study, share, and modify the software. The license was the first copyleft for general u ...

license. Majority of the library is written in C# and thus cross-platform. Functionality of AForge.NET has been extended by the Accord.NET library. ; Accord.NET: another computer vision and artificial intelligence library, available under the

Gnu Lesser General Public License The GNU Lesser General Public License (LGPL) is a free-software license published by the Free Software Foundation (FSF). The license allows developers and companies to use and integrate a software component released under the LGPL into their ow ...

, version 2.1. It is mainly written in C#.

Graphical user interface

; Gtk#: C# wrappers around the underlying

GTK+ GTK (formerly GIMP ToolKit and GTK+) is a free and open-source cross-platform widget toolkit for creating graphical user interfaces (GUIs). It is licensed under the terms of the GNU Lesser General Public License, allowing both free and propriet ...

and

GNOME A gnome is a mythological creature and diminutive spirit in Renaissance magic and alchemy, first introduced by Paracelsus in the 16th century and later adopted by more recent authors including those of modern fantasy literature. Its character ...

libraries, written in C and available on Linux, MacOS and Windows. ;

(WinForms): Microsoft GUI framework. The original Microsoft implementation runs on Windows operating systems and provides access to Windows User Interface Common Controls by

wrapping Wrapping may refer to: *Buddy wrapping, the act of bandaging a damaged (particularly a fractured) finger or toe together with a healthy one *Overwrap, a wrapping of items in a package of a wrapping over packaging *Wrapping (graphics), the process ...

the

Windows API The Windows API, informally WinAPI, is Microsoft's core set of application programming interfaces (APIs) available in the Microsoft Windows operating systems. The name Windows API collectively refers to several different platform implementations th ...

managed code Managed code is computer program code that requires and will execute only under the management of a Common Language Infrastructure (CLI); Virtual Execution System (VES); virtual machine, e.g. .NET, CoreFX, or .NET Framework; Common Language Ru ...

. The alternative Mono implementation is open source and cross-platform (it runs on Windows, Linux, Unix and OS X). It is mainly compatible with the original implementation but not completely. The library is written in C# in order to avoid Windows dependence. :At the Microsoft Connect event on December 4, 2018,

Microsoft Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washingt ...

announced releasing of Windows Forms as open sourc
project on GitHub
It is released under the

MIT License The MIT License is a permissive free software license originating at the Massachusetts Institute of Technology (MIT) in the late 1980s. As a permissive license, it puts only very limited restriction on reuse and has, therefore, high license comp ...

. Windows Forms has become available for projects targeting the .NET framework. However, the framework is still available only on Windows platform and the Mono incomplete implementation of WinForms remains the only cross-platform implementation. ;

(WPF): a graphical subsystem for rendering user interfaces in Windows-based applications by Microsoft. It is based on

DirectX Microsoft DirectX is a collection of application programming interfaces (APIs) for handling tasks related to multimedia, especially game programming and video, on Microsoft platforms. Originally, the names of these APIs all began with "Direct", ...

and employs XAML, an XML-based language, to define and link various interface elements.MSDN.NET Development: WPF: XAML Overview
/ref> WPF applications can be deployed as standalone desktop programs or hosted as an embedded object in a website. :At the Microsoft Connect event on December 4, 2018,

announced releasing of WPF as open sourc
project on GitHub
It is released under the

. Windows Presentation Foundation has become available for projects targeting the .NET framework. However, the system is still available only on Windows platform. ;

Windows UI Library Windows UI Library (WinUI codenamed "Jupiter", and also known as UWP XAML and WinRT XAML) is a user interface API that is part of the Windows Runtime programming model that forms the backbone of Universal Windows Platform apps (formerly known ...

(WinUI): a set of Microsoft UI controls and features for the

(UWP). At the Microsoft Connect event on December 4, 2018,

announced releasing of WinUI as open sourc
project on GitHub
WinUI has become available for projects targeting the .NET framework. It is released under the

. However, the library is still available only on Windows platform. ; Xamarin.Forms: a cross-platform UI toolkit for development of native user interfaces that can be run on macOS, iOS, Android, and Universal Windows Platform apps. ; .NET Multi-platform App UI (.NET MAUI): a cross-platform UI toolkit announced in May 2020 that originated as a fork of Xamarin.Forms and that can run on Android, iOS, Linux, macOS, Tizen, and Windows. .NET MAUI will run on

.NET 6 The domain name net is a generic top-level domain (gTLD) used in the Domain Name System of the Internet. The name is derived from the word ''network'', indicating it was originally intended for organizations involved in networking technologies ...

and later. The source code is licensed under

and available on

GitHub GitHub, Inc. () is an Internet hosting service for software development and version control using Git. It provides the distributed version control of Git plus access control, bug tracking, software feature requests, task management, continuous ...

Quality assurance

; NUnit: an

open source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use the source code, design documents, or content of the product. The open-source model is a decentralized sof ...

unit testing In computer programming, unit testing is a software testing method by which individual units of source code—sets of one or more computer program modules together with associated control data, usage procedures, and operating procedures&md ...

framework A framework is a generic term commonly referring to an essential supporting structure which other things are built on top of. Framework may refer to: Computing * Application framework, used to implement the structure of an application for an op ...

for .NET, written in C# and thus cross-platform. It is one of many programs in the

xUnit xUnit is the collective name for several unit testing frameworks that derive their structure and functionality from Smalltalk's SUnit. ''SUnit'', designed by Kent Beck in 1998, was written in a highly structured object-oriented style, which len ...

family. Licensed under

Object–relational mapping

.NET Framework natively provides utilities for

object–relational mapping Object–relational mapping (ORM, O/RM, and O/R mapping tool) in computer science is a programming technique for converting data between type systems using object-oriented programming languages. This creates, in effect, a "virtual object databas ...

through ADO.NET, a part of .NET stack since .NET 1.0. In addition, a number of third-party object–relational libraries have emerged, especially in earlier years of the .NET development, in order to fill some perceived gaps of the framework. As the framework has evolved, additional object–relational tools were added, such as the

Entity Framework Entity Framework (EF) is an open source object–relational mapping (ORM) framework for ADO.NET. It was originally shipped as an integral part of .NET Framework, however starting with Entity Framework version 6.0 it has been delivered separately ...

included with the .NET Framework 3.5. LINQ to SQL was also introduced with .NET 3.5. This somehow reduced significance and popularity of third-party object–relational libraries. ;

: an open source

(ORM) framework for ADO.NET. It was a part of

, but since Entity framework version 6 it is separated from .NET framework. ;

NHibernate NHibernate is an object–relational mapping (ORM) solution for the Microsoft .NET platform. It provides a framework for mapping an object-oriented domain model to a traditional relational database. Its purpose is to relieve the developer from ...

:NHibernate is an object–relational mapper for the .NET platform.

Notes

References

External links

General:
.NET Open Source Developer Projects
a list maintained at

Numerical libraries:
The Math Forum - Math Libraries
an extensive list of mathematical libraries with short descriptions
Guide - Math and Statistics Programming with F#
Data:
Object Relational Mapping

Comparison of Object Relational Mapping Tools for the .NET Framework
{{Common Language Infrastructure .NET software Programming tools .NET libraries and frameworks Computer libraries Numerical libraries Graphics libraries Free and open-source software