Note that the ELM327 can handle communication over multiple protocols, not just CAN:
Protocol - Description 0 - Automatic 1 - SAE J1850 PWM (41.6 kbaud) 2 - SAE J1850 PWM (10.4 kbaud) 4 - ISO 9141-2 (5 baud init) 5 - ISO 14230-4 KWP (5 baud init) 6 - ISO 14230-4 KWP (fast init) 7 - ISO 15765-4 CAN (11 bit ID, 500 kbaud) 8 - ISO 15765-4 CAN (29 bit ID, 500 kbaud) 9 - ISO 15765-4 CAN (11 bit ID, 250 kbaud) A - ISO 15765-4 CAN (29 bit ID, 250 kbaud) B - User1 CAN (11* bit ID, 125* kbaud) C - User2 CAN (11* bit ID, 50* kbaud)
Source: above mentioned link.