Infer.NET is a free and open source .NET software library for machine learning.

[2] It supports running Bayesian inference in graphical models and can also be used for probabilistic programming.

The framework is used in various different domains such as bioinformatics, epidemiology, computer vision, and information retrieval.

[4][5] Development of the framework was started by a team at Microsoft’s research centre in Cambridge, UK in 2004.

[6][7] Infer.NET is used internally at Microsoft as the machine learning engine in some of their products such as Office, Azure, and Xbox.