Business Process Modelling Notation (BPMN) is standard way to visually depict business process.The primary goal of BPMN is to provide a standard notation that is readily understandable by all business stakeholders. These business stakeholders include business analysts who create and refine the processes, technical developers responsible for implementing the processes, and business managers who monitor and manage the processes. Before BPMN there was really no common language to express visually a business process, various tools and symbols were used but it was not understood by all unless it was explained and the Idea behind BPMN is to create a standard, no matter what tool u work in and who ever prepares the model but it will be universally understood by anyone who prepares or know about BPMN. So it is as great way to standardise on how we visualise processes.
Business Process Modeling Notation (BPMN) is a standard for business process modeling. It provides a graphical notation for specifying business processes in a Business Process Diagram (BPD). Consequently, BPMN is intended to serve as common language to bridge the communication gap that frequently occurs between business process design and implementation.
The following few symbols is from basic flow chart which is used to draw BPMN
the rounded rectangle states the process has started
The rectangle box represents the process / activity of the business
Diamond shape states that the decision of the business activity.
and the arrow/connector represents the flow from one activity to another.
No matter what tool you use these basic symbol and their behaviors is understood universally. BPMN makes easier the communication and coordination between non-technical and technical users by offering a common language.