ReasonML, a syntax extension for OCaml created by Facebook, builds on the established functional programming language to tackle real-world problems in production environments, much like React, with which it shares a creator. It supports both native and JavaScript as compile targets, facilitating code that can run anywhere, and utilizes the BuckleScript project for compiling into JavaScript. Reason's strong type system reduces runtime errors by converting them into compile-time issues, simplifying refactoring and enhancing development efficiency. It emphasizes immutable data structures by default, though it allows for controlled mutation when necessary, balancing functional purity with practical imperative programming needs. The language's syntax is designed to be approachable for JavaScript developers, offering features like automatic currying and pattern matching, which streamline code readability and error handling. ReasonML's pragmatic approach and strong typing provide a robust framework for developers, reducing the likelihood of runtime errors while maintaining flexibility for practical coding solutions.