, Kestrel and IIS (Internet Information Services) are both web server options in the Microsoft ecosystem, but they serve different purposes and have different characteristics.Kestrel:Purpose: Kestrel is a lightweight, cross-platform web server developed by Microsoft. It is designed to be used as the default web server for ASP.NET Core applications. Characteristics: Cross-Platform: Kestrel is cross-platform and can run on Windows, Linux, and macOS. Lightweight: It is a lightweight and efficient web server that is optimized for hosting ASP.NET Core applications. Integration: While Kestrel is often used in conjunction with other web servers, such as IIS or Nginx, it can also be used as a standalone server. IIS (Internet Information Services):Purpose: IIS is a full-featured web server developed by Microsoft and is primarily used for hosting traditional ASP.NET applications, as well as other types of web applications. Characteristics: Windows-Centric: IIS is closely tied to the Windows operating system and is the default web server for Windows servers. Feature-Rich: It provides a wide range of features, including support for various web technologies, application pools, security features, and more. Integration: IIS can be used in conjunction with other web servers, such as Kestrel, to provide additional features like load balancing, reverse proxying, and SSL termination. Differences:Use Cases: Kestrel is often used as the default web server for hosting ASP.NET Core applications, while IIS is used for hosting a broader range of web applications, including traditional ASP.NET applications. Platform Support: Kestrel is cross-platform and can run on different operating systems, while IIS is primarily designed for Windows servers. Footprint: Kestrel is lightweight and designed for performance in the context of ASP.NET Core applications, while IIS is a more feature-rich server with a broader set of functionalities. In practice, it's common to use IIS as a reverse proxy in front of Kestrel to take advantage of IIS's features while benefiting from Kestrel's performance for serving ASP.NET Core applications. However, the specific use cases and integrations may vary based on the requirements of the application and the hosting environment.