98-tan is an anthropomorphized character representing the Windows 98 operating system in the OS-tan series, a Japanese internet meme where various operating systems are personified as cute girls. She is often depicted as a helpful, energetic, and somewhat clumsy girl, reflecting the popularity and occasional instability of Windows 98. 98-tan typically wears a green dress and is known for her friendly demeanor. In the OS-tan universe, she serves as a big sister figure to other Windows-tans and plays a central role in their interactions.