The Metropolitan Transportation Authority (MTA) operates a number of bus routes in Brooklyn, New York, United States; one minor route is privately operated under a city franchise. Many of them are the direct descendants of streetcar lines (see list of streetcar lines in Brooklyn); the ones that started out as bus routes were almost all operated by the Brooklyn Bus Corporation, a subsidiary of the Brooklyn–Manhattan Transit Corporation, until the New York City Board of Transportation took over on June 5, 1940. Of the 55 local Brooklyn routes operated by the New York City Transit Authority, roughly 35 are the direct descendants of one or more streetcar lines, and most of the others were introduced in full or in part as new bus routes by the 1930s. Only the eastern section of the B82 (then the B50), the B83, and the B84 were created by New York City Transit from scratch, in 1978, 1966, and 2013, respectively.
This table gives details for the routes prefixed with "B" - in other words, those considered to run primarily in Brooklyn by the MTA. For details on routes with other prefixes, see the following articles:
Routes that operate at all times: B1, B3, B6, B8, B12, B14, B15, B17, B25, B26, B35, B36, B38, B41, B42, B43, B44, B46, B47, B48, B52, B54, B60, B61, B62, B63, B68, B82