Since the time ancient genealogy has been recorded and passed down throughout history, it seems that it may have been passed down by word of mouth from one generation to another or included in storytelling. Once paper and pen became available, the family lineage was written down for safekeeping. Sense then various cultures traces their origins in different ways based on their characteristics and traditions.
For instance, the Native Americans trace their origins much differently than do the ancient Greeks. The ancient Greeks believed they were descendants of the Gods. Family lineage became increasingly important during the medieval times, since the inheritance of title and land was very significant.
There are different forms and formats of family trees. You should use the best family linage format for you and your purposes. For instance, many individuals can easily follow a descendents chart, which names the patriarch and matriarch at the top and then will branch downward showing the family descendents. An ancestry chart starts at the bottom and then branches upwards and outwards including more ancestors. However, family charts may also branch from the left side and branch out to the right.