Express TypeScript is an integration of Express.js, a minimalist web application framework, with TypeScript, a statically typed superset of JavaScript, aimed at enhancing error detection, code quality, and developer productivity. This combination leverages TypeScript's static typing and rich IDE support, resulting in a more robust and streamlined development experience that reduces runtime errors and facilitates easier code maintenance. Setting up an Express TypeScript environment involves installing Node.js, Express.js, and TypeScript, along with an IDE like Visual Studio Code for efficient coding. Developers can create a simple API and build applications using this setup, benefiting from TypeScript's advanced features such as middleware usage, error handling, and testing. While there may be a learning curve for newcomers, the integration ultimately leads to improved web application development by making the code more secure and maintainable over time.