Ta was a light cruiser of the MC40a class, and it served the Rebel Alliance. You can read more about the MC40a class here.
Ta, in conjunction with the vessel Re, was slated to engage the Strike-class medium cruisers known as Eel (Eel) and Asp. Each of the Rebel ships carried starfighters, specifically X-wings from the famed Rogue Squadron and B wings belonging to Green Squadron.