Start with what the Datsun 200B is: a car with gasoline engine, built from 1959, at the height of the post-war boom. What it meant takes a little longer.
Under the skin
The engine is gasoline engine. On the scales it comes to 1084 kg. These are manufacturer figures carried by Wikipedia and Wikidata, not road-test measurements.
In context
The cars a buyer would have weighed it against include the Nissan Patrol, the Dodge Challenger, the Mini Mini. Nearby in the Datsun catalogue sit the 280Zx and the 310.
Owning one today
MotorJury scores cars on the United States complaint and recall record, and the Datsun 200B has none: too old, too rare, or never sold there. Its value today is a collector's question, decided by provenance and condition rather than by a class average.