With an “Association” you make a connection (association) between the classes. So in this example you first click on the “Association” button in the “Class” list of the toolbox. Then you click on the frame of 1 of the classes, drag the mouse pointer to the frame of the other class and then release the mouse button.

In the “Properties” window you can enter a name next to “Name”. This name describes the association.

You can also indicate for the association how many classes can be used in the association. In the “Properties” window you can specify in the “(End1)” section after “Mulitiplicity” how many classes can be connected (zero-to-one, one, zero-to-infinity, one-to-infinity, infinite) . You can also set the “Multiplicity” for “(End2)”.

An example of an association. A Leraar (teacher) teaches one or more vakken (subjects, courses). A subject is taught by one Leraar (teacher).