Uit ArchiMate:"A business process describes the internal behavior performed by a business role that is required to produce a set of products and services. For a consumer the products and services are relevant and the required behavior is merely a black box, hence the designation “internal”.
In comparison to a business interaction, in which a collaboration of two or more business roles are (interactively) involved, at a given level of granularity only one business role is involved with a business process. However, a complex business process may be an aggregation of other, finer-grained processes, each of which may be assigned to finer-grained roles that are aggregated by roles that are aggregated by the original role.
There is a potential many-to-many relationship between business processes and business functions. Informally speaking, processes describe some kind of “flow” of activities, whereas functions group activities according to required skills, knowledge, resources, etc.
A business process may be triggered by, or trigger, any other business behavior element (e.g., business event, business process, business function, or business interaction). A business process may access business objects. A business process may realize one or more business services and may use (internal) business services or application services. A business role or an application component may be assigned to a business process to perform this process manually or automated, respectively. The name of a business process should preferably be a verb in the simple present tense; e.g., 'handle claim'.
In an ArchiMate model, the existence of business processes is depicted. It does not, however, list the flow of activities in detail. During business process modeling, a business process can be expanded using a business process design language; e.g., BPMN."