F## is a programming language that is part of the F# family, designed for functional-first programming. It is a multi-paradigm language that supports functional, imperative, and object-oriented programming styles. F## is known for its strong type inference, which helps developers write safer and more efficient code without excessive type annotations. F## is often used in data science, web development, and financial modeling due to its powerful capabilities for handling complex data structures. It runs on the Common Language Runtime (CLR) and is compatible with the Microsoft .NET ecosystem, allowing developers to leverage existing libraries and tools.