On-Board Diagnostics [OBD] is a vehicle bus used to monitor engine functions. OBD II is the second generation of that interface. The graphic below details a Right Angle OBDII male connector to female DB9 pin Cable assembly
Right Angle OBDII connector to female DB9 Connector
The OBDII connector is the automotive end of the cable, the DB15 could connect to any interface with a mate [one with male pins].
This is one of a number of pages showing OBDII cable assemblies
OBDII to DB15 pin Cable assembly
Female OBDII to VW 2x2 pin Cable assembly [Volkswagen]
Male OBDII to DB9-pin Cable right angle
Male OBDII to Male DB9-pin Cable assembly
Male OBDII to Male DB15-pin Cable assembly
Male OBDII to Female OBDII Cable assembly
BMW to Female OBDII Cable assembly [Bavarian Motor Works]
Main OBDII page; OBDII description, Signal Assignments; OBDII pinout
Vehicle Buses; Automotive Bus descriptions