Table options – Data fields.
One data field contains one characteristic of an object: a person's name, an event date, etc. In the tables all data fields are arranged in columns, one field in one column. Table options – Data fields calls data fields options box:

It allows to create, edit and delete data fields. Only fields created by a user can be deleted. The checked fields become visible in the table. The order of the columns in the table corresponds to the order of the fields in the list. The actions Move up or Move down as well as dragging fields allow to change the order of the fields in this list. The action Restore restores standard order and visibility of the fields.

Agelong Tree allows to create user's data fields of different types:

Use autocomplete option turns on the automatic completion suggestions. Can be used in full name option is used to include a field into the full name (as additional to First name, Second name, etc) in program options.
Scope specifies types of objects for which this field is relevant (for persons it’s Men and Women).
If the Always show in edit window option is on, this field will be displayed in the list of data fields when the object is edited even if the field does not contain any value.

It is also possible to create data fields that belong to a certain event type only (see events types).