The Starfarer differs from traditional bulk freighters in one key way: it is a dedicated fuel platform. The Starfarer is designed not only to load, store, and protect fuel stasis units, but it is also designed to take in spaceborne gases and refine them for use without landing. And while it excels at this, the Starfarer can also be used to ferry traditional bulk cargo pods. The listed Cargo Capacity is only for the dedicated Cargo Room and does not account for the extra space available from the bulk cargo pods.
The Starfarer is a tanker developed by Musashi Industrial Starflight Concern (MISC). Starfarers are a common sight throughout the United Empire of Earth (UEE), performing fuel-related roles such as simple transport, in-flight refueling, and the collection and refining of fuel from spaceborne sources, among other functions. The UEE military operates a hardened variant produced under license by Aegis Dynamics called the Starfarer Gemini
Here is a short history of publications about the series from the RSI website.
First Look: Starfarer Tanker
Party Time and Final 24 Hour Announcements!
Letter from the Chairman: $31 Million
MISC Starfarer Now Available!
This is an excellent video of the history of the Musashi Indistrial & Starflight Concern (MISC) company from in-game lore, by The AstroPub. Please subscribe to his channel as he produces the most thorough and best Star Citizen lore content.