What is GEDCOM?
GEDCOM (an acronym for GEnealogical Data COMmunication), is the standard for exchanging data from one genealogy program to another.
A GEDCOM file is an text file, usually with the extension .GED, which preserves the relationships in a genealogy data file. Most genealogy programs have the ability to import and export data as GEDCOM files. If a lineage-linked genealogy program cannot do that, it is probably not worth using.