There is a pasta shape that Romans will fight about. Not politely disagree. Fight. The bucatini question, which to the uninitiated seems like a narrow culinary preference, is in Rome a matter of identity, loyalty, and occasionally volume. Get the wrong bucatini for an amatriciana and you will hear about it. Serve spaghetti instead and you may not be invited back.
The shape itself seems simple: a long, thick strand of pasta with a hole running through the center. Bucato in Italian means pierced or hollow, which is where the name comes from. The hole is approximately 1.5 to 2 millimeters in diameter. It looks like a detail. It is not a detail. It is the entire point.
