About Event Versions
When you create and activate an activity, it is saved, and its corresponding Event, as a version. Any changes later made to this activity are also saved, and a new version of the Event is created.
In the Segment Builder you can choose to use the previous or present version of the activity's Event for your Segment.
When you create a Segment with one of these Events, you'll notice a Version drop-down menu where you can select the version of the Event.
Forms Events Versions
If at some point you edit your Form to start collecting a new Attribute, or remove a field from the Form, a new version of the Forms - Submit Event is created to match your changes.
Custom Events Versions
If you remove any Event data fields from the Custom Event you previously created in Data Model, or add a new field, a new version of your Custom Event will be created.
Product View Event Versions
If you remove or map a new visual element in your Product Views activity, a new version of Product Views - Collect Event will be created.