Microsoft's Internet Information Services

Microsoft's Internet Information Services (IIS) is a web server software that runs on the Windows operating system. It is included with most Windows Server editions and provides a platform for hosting websites, web applications, and other web-based content.

IIS supports a wide range of web protocols and technologies, including HTTP, HTTPS, FTP, SMTP, and WebSockets. It also supports ASP.NET, Microsoft's server-side web application framework, and can be used with other programming languages like PHP, Python, and Ruby.

IIS offers various features and tools for managing web applications and websites, including a web-based management console, integrated support for Windows authentication and Active Directory, and advanced logging and monitoring capabilities. It also includes a powerful URL rewriting module for configuring and managing custom URL rewriting rules.

While IIS is not an open-source web server like Apache or Nginx, it is widely used in enterprise environments and offers a range of enterprise-grade features and integrations with other Microsoft technologies.