Activities are nodes where interaction or actions occur. Such instances could either be a human action or a system event. For example, an activity could be a user being asked to fill in a form; or it could be a system notification that needs to be sent out when triggered by some event.
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In your Workflow Designer, click on the Activity element icon on the left toolbar element menu and then click on the Requestor swimlane. This will add an activity for your Requestor. To To change the activity name from "Activity 1" to "Apply leave", click on the Selection element icon on the left toolbar element menu and then double-click on Activity 1 in the swimlane. In the resulting dialog box, change "Activity 1" to "Apply leave" in the Name field.
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