Artifacts allow you to show additional information about a Process i.e. how data, documents and other objects are used and updated during the business process. Artifacts are not directly related to sequence, or message flow, of the process.
Data Objects are documents or other types of data, that show how data are used during a business process. Data objects can be used to define the input and output of data to/from activities.
To create an Association between a Data Object and a Flow control:
1.Click the Association handle of the Data Object (on the left of the object).
2.Drag the connector onto the Flow Control object which is highlighted when you can drop it.
Text Annotations allow you to annotate various sections of a business process and are connected to the specific object using an association.
Groups are often used to highlight certain sections of a diagram, even across different pools. Groups cannot connect to a sequence or message flow. Group objects are generally placed behind task or process objects in the diagram.