Processes sometimes need to wait for an event outside the process to occur before continuing. These events are fired from:
• Notifications from other processes currently running and
• Notifications from outside applications or web pages.
• This friction built into the process is handled using an activity called a Notification Wait activity (envelope going into a box).
In this example, the instance in the process will remain in the Wait for Supplier Ok activity until it has been notified from outside the process. The event causing the notification sends in information in this example to let the process know if the product was in stock. Based on this, the instance will travel through either the conditional transition (product not in stock) or the unconditional transition.