A set of graphical standards that specify the symbol sets that will be used in BPM diagrams/models. As such, they define the symbols that will be used in depicting process and workflow in business modeling.
Created by the Business Process Management Initiative, now merged with the Object Management Group (OMG), an information systems standards setting group, BPMN has growing acceptance as a standard from many perspectives, which has resulted in its inclusion in several of the most widely used modeling tools. It provides a robust symbol set for modeling different aspects of business processes. Like most modern notations, the symbols describe definite relationships such as workflow and order of precedence.
In addition to symbol standardization, BPMN attempts to standardize terminology and modeling technique. It serves a purpose similar to the Event Process Chain (EPC) notation used in the ARIS methodology.
This standard has gone through several iterations, the latest being 2.0. However, the standard will continue to be modified and the version number and content will change. It is anticipated that the BPM modeling tool vendors and BPMS vendors will adjust to the standards as they change.
Although BPMN provides a set of standard modeling symbols, most organizations will still need to apply their own architectural and engineering standards to have a complete BPM modeling solution.
Source: Guide to the Business Process Management Body of Knowledge – ABPMP BPM CBOK V3.0.