The F# language is nowadays described as a 'functional-first' programming language. Is this just a marketing trick to make you think that F# is somehow special, or does the F# style of programming really differ from other functional languages enough that it is worth using a new 'functional- first' label? I will try to give you an answer in this talk! Expect a mix of practical hands-on code samples that illustrate the F# style of programming, ramblings on the philosophy behind F#, and extracts from case studies based on large projects completed using the F# language. Tomas is a computer scientist and open-source developer. He is a visiting researcher at the Alan Turing Institute, working on tools for open data-driven storytelling. He wrote the popular book, Real-World Functional Programming and is a lead developer of several F# open-source libraries. He is a partner at fsharpWorks where he provides trainings and consulting services. Tomas' PhD thesis at the University of Cambridge focused on context-aware programming, but his most recent writings also includes two essays, which try to understand programming through the perspective of philosophy of science.