OS-tan

thumb|Box art of Windows 8.1 Pro DSP Memorial Pack with a group of OS-tans from left to right: Claudia (Microsoft Azure), Yuu and Ai ([[Windows 8.1), and Nanami Madobe (Windows 7).]] OS-tans are moe anthropomorphic personifications of popular operating systems, originating on the Japanese imageboard Futaba Channel. The designs of the OS-tans, which were created by various amateur Japanese artists, are typically female; for example, the personifications of Microsoft Windows operating systems are often depicted as sisters of varying ages. The -tan element in the term is a hypocoristic suffix in Japanese that implies extremely youthful endearment.

Though initially appearing only in fan works, the OS-tans proved popular enough that Microsoft branches in Asian countries such as Singapore, Hong Kong, Macau, Taiwan and Japan used the OS-tan personification concept as the basis for advertising campaigns for Microsoft Windows, Internet Explorer and Microsoft Silverlight, respectively.