There are dozens of different genealogy numbering systems. Sosa-Stradonitz, Register, Henry, D'Aboville, and many others. Many are useful for ancestor reports, and many for descendant reports. Some combined systems are used for a combined ancestor/descendant (i.e. relative) report. But none of them can be relied on to retain the same numbering with the addition of a newly found individual. The new individual may get a previously assigned number, and many previously assigned numbers will have to be reassigned. As a result, you should never use a numbering of ancestors/descendants as your primary reference to the individuals in your family.
Behold magnifies the problem. Since Behold is very flexible in allowing you to move families and lines within each family, it is impossible for any numbering system to retain the same numbers through these transformations. Every reorganization of individuals in Behold will result in a different number.
Therefore the philosophy in Behold is to use numbering to help you simply:
Identify which family the person is in,
Identify where in the family the person is, and
Make it easy in a printed version of the Everything Report, to use links to find a person.
To do this, Behold by default uses a simple two-level numbering system, with a family prefix and a number representing the person in that family incremented in a sequential manner from first to last. This method especially helps you in printouts, where you don't have access to the live hyperlinks to find people.
To customize the numbering, go to the Organize Numbering page and check out the IDs and Numbers section:
You have several choices, and the preview will give you an example of what a typical number will look like.
Generally, you will want to keep your numbering short. For the minimalist, you can just number everyone sequentially by choosing "DesNum" from the drop-down box. But you will end up like having the family ID prefix there to help identify the family.
Family IDs are assigned automatically by behold based on the surname of the central individual for the family. If more than one family surname starts with the same letters, then a number is added at the end to distinguish the family IDs. You can edit the individual family IDs yourself on the Organize Families page.