Metro UI is a design language developed by Microsoft that emphasizes a clean, minimalist aesthetic. It features bold typography, flat icons, and a grid-based layout, making it easy for users to navigate and interact with applications. The design is optimized for touchscreens, promoting a seamless experience across devices. Introduced with Windows 8, Metro UI aimed to unify the user experience across various platforms, including Windows Phone and Xbox. Its focus on simplicity and functionality allows users to quickly access information and applications, enhancing overall usability in a digital environment.