Modern UI

Metro, (officially known as Microsoft design language or MDL), is a design language created by Microsoft. This design language is focused on typography and simplified icons, absence of clutter, increased content to ratio ("content before chrome"), and basic geometric shapes. Early examples of Metro principles can be found in Encarta 95 and MSN 2.0. The design language evolved in Windows Media Center and Zune and was formally introduced as "Metro" during the unveiling of Windows Phone 7. It has since been incorporated into several of the company's other products, including the Xbox 360 system software, Xbox One, Windows 8, Windows Phone, and Outlook.com. Before the "Microsoft design language" title becomes official, Qi Lu, referred to it as the modern UI design language in his MIXX conference keynote speech.According to Microsoft, "Metro" has always been a codename and was never meant as a final product, but news websites attribute this change to a trademark issues.

Microsoft Design Language 2 (MDL2) was developed alongside Windows 10. Later, the Fluent Design language extended it.

The design language is based on the design principles of classic Swiss graphic design. Early glimpses of this style could be seen in Windows Media Center for Windows XP Media Center Edition, which favored text as the primary form of navigation. This interface carried over into later iterations of Media Center. In 2006, Zune refreshed its interface using these principles. Microsoft designers decided to redesign the interface and with more focus on clean typography and less on UI chrome. These principles and the new Zune UI were carried over to Windows Phone (from which much was drawn for Windows 8). The Zune Desktop Client was also redesigned with an emphasis on typography and clean design that was different from the Zune's previous Portable Media Center based UI. Flat colored "live tiles" were introduced into the design language during the early Windows Phone's studies.

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