2003 Server is often portrayed as being half-girl, half-fish, with an ethernet hub as a bonnet on her head. Other versions show her as a girl with a short white skirt and a vest-style top with a long tail in the back (usually with a bow) and Windows four-square logo pins in the bow at her neck and on the tail. In some forms, she has a belt made from ethernet cable wrapped around her waist. Saba is a pun: in Japanese, the word for server is pronounced saaba, while saba is the word for mackerel.
Saba-tan is constantly being eaten by cats (As another gag of the fact that she's a fish), also in one episode, Windows 95 is seen cooking Saba-tan for lunch, she has been gutted, stunned, and placed on a cutting board as 95 is seen with a sharp knife, preparing to chop Saba-tan up and cook her for ME and 2K to eat. It is still unknown how she escaped that situation since she was unconscious while 95 held the knife up ready to chop her up.
Also in the picture of all the OS-tans, she is seen becoming a cats lunch, however she returns in a later comic, indicating that she somehow escaped being eaten for lunch, or the fact that there are many Saba OS-tans in the OS-tan universe.