CAN, which was developed by Bosch in the early 1980's and became an international standard (ISO 11898) in 1994, was specially developed for fast serial data exchange between electronic controllers in motor vehicles. This is precisely how CAN can also be used in the implementation of industrial microcontroller networks, e.g. as an internal bus in machine tools, to interconnect distributed measurement, control and monitoring functions on the lowest automation level to a higher-level computer, or as a field bus to interconnect sensors, actuators and/or user interfaces.
The ISO 11898 standard describes the physical and the data link layer. The lower protocol levels of CAN (layer 1 and 2) are standardized in the ISO/OSI layer model. Protocols based on layer 7 (application layer) are summarized in different, partly manufacturer-specific standards. Examples for these CAN-based protocols are CANopen, DeviceNet, J1939 and LIN.
The specification can be obtained in PDF format from www.iso.org. The CAN 2.0 specification is available for download from the Bosch website. For more detailed info about CAN in general, you can have a look at M.J. Schofield's CAN Introduction, at the website of the CAN Mailing List (canlist) or contact sales@vector-worldwide.com.