# Ur/Web > functional programming language tailored for web development **Wikidata**: [Q18711761](https://www.wikidata.org/wiki/Q18711761) **Wikipedia**: [English](https://en.wikipedia.org/wiki/Ur_(programming_language)) **Source**: https://4ort.xyz/entity/ur-web ## Summary Ur/Web is a functional programming language specifically designed for web development. It enables developers to write type-safe web applications by integrating client-side and server-side logic within a single language framework. The language emphasizes correctness and safety through its strong static type system. ## Key Facts - Ur/Web is a functional programming language tailored for web development. - It was created in December 2014. - The stable version is 20200209, released on February 9, 2020. - File extensions include `.ur`, `.urs`, and `.urp`. - It is influenced by Standard ML and ML. - The official website is http://impredicative.com/ur. - It is classified as an instance of a programming language. - It has aliases including "Ur". - It is referenced on Quora under the topic "Ur-programming-language". - It is documented on Wikipedia in multiple languages: Catalan (ca), English (en), Chinese (zh), and Cantonese (zh_yue). - Sitelink count across platforms is 4. - Freebase ID: /m/012lmpn7 ## FAQs ### What is Ur/Web used for? Ur/Web is a functional programming language designed for building web applications. It allows developers to write both frontend and backend components in a single language, ensuring type safety and reducing errors. ### When was Ur/Web created? Ur/Web was created in December 2014. ### What programming languages influenced Ur/Web? Ur/Web was influenced by Standard ML and ML. ### What file extensions are associated with Ur/Web? The file extensions used by Ur/Web are `.ur`, `.urs`, and `.urp`. ### Is Ur/Web free to use? Yes, Ur/Web is a free and open-source programming language. ### Where can I find more information about Ur/Web? The official website for Ur/Web is http://impredicative.com/ur. ### Is there a community or documentation available for Ur/Web? Yes, it is documented on Wikipedia in multiple languages and has a presence on Quora. ## Why It Matters Ur/Web matters because it addresses the complexity and error-proneness of traditional web development by unifying client and server logic under one type-safe functional language. This reduces the potential for runtime errors and improves developer productivity. Its design philosophy emphasizes correctness, making it particularly valuable in environments where reliability is critical. By leveraging functional programming paradigms and strong static typing, Ur/Web sets a high standard for safe and maintainable web applications. ## Notable For - Being a functional programming language tailored for web development. - Integrating client and server logic in a single language. - Using strong static typing to prevent common web development errors. - Being influenced by ML and Standard ML, inheriting their strong type systems. - Supporting a unified approach to web programming that reduces complexity. - Having a stable version as of February 9, 2020. - Being documented across multiple language versions of Wikipedia. ## Body ### History Ur/Web was created in December 2014 as a functional programming language tailored for web development. It was designed to address the challenges of building safe and reliable web applications by leveraging strong static typing and functional programming principles. The language draws influence from ML and Standard ML, both known for their robust type systems and functional paradigms. ### Architecture Ur/Web enables developers to write both frontend and backend components in a single language. This unified approach ensures that the entire application is type-checked end-to-end, reducing runtime errors and increasing reliability. The language enforces correctness by construction, making it particularly suitable for applications where safety and correctness are paramount. ### Ecosystem The ecosystem of Ur/Web includes: - File extensions: `.ur` (source files), `.urs` (signature files), and `.urp` (project files). - A stable version (20200209) was released on February 9, 2020. - The official website is http://impredicative.com/ur, which serves as the central hub for documentation and resources. ### Community and Documentation Ur/Web has limited but dedicated documentation and community presence: - It is documented on Wikipedia in multiple languages including Catalan, English, Chinese, and Cantonese. - It has a Quora topic under "Ur-programming-language". - The sitelink count across platforms is 4, indicating a niche but specialized user base. ### Related Projects and Influences Ur/Web is directly influenced by: - **Standard ML (SML)**: A functional programming language known for its strong module system. - **ML**: A family of functional programming languages originating in 1973, known for influencing type systems in modern languages. These influences are evident in Ur/Web’s emphasis on type safety and functional programming paradigms. ### Technical Specifications - **Inception**: December 2014 - **Stable Version**: 20200209 (released February 9, 2020) - **File Extensions**: `.ur`, `.urs`, `.urp` - **Website**: http://impredicative.com/ur - **Aliases**: Ur - **Instance Of**: Programming Language - **Influenced By**: Standard ML, ML - **Freebase ID**: /m/012lmpn7 - **Quora Topic**: Ur-programming-language - **Wikipedia Languages**: ca, en, zh, zh_yue - **Sitelink Count**: 4 ### Classification and Identity Ur/Web is classified as a programming language, specifically tailored for web development. It is recognized on platforms such as Wikidata, Freebase, and Quora. Its identity is further solidified by its dedicated website and presence in multilingual Wikipedia entries. ## References 1. Quora