"GEDCOM is an acronym for GEnea-logical Data COMmunication.
"GEDCOM is a specification for exchanging genealogical data between different genealogy software. GEDCOM was developed by The Church of Jesus Christ of Latter-day Saints as an aid to genealogical research.
A GEDCOM file is plain text (usually either ANSEL or ASCII) containing genealogical information about individuals, and meta data linking these records together. Most genealogy software supports importing from and/or exporting to GEDCOM format. However, some genealogy software programs incorporate the use of proprietary extensions to the GEDCOM format, which are not always recognized by other genealogy programs. The GEDCOM TestBook Project evaluates how well popular genealogy programs conform to the GEDCOM 5.5 standard. Additionally, many tools exist to convert GEDCOM files to HTML pages." - Wikipdeia
Most of the genealogical data on this site is extracted from my JACKLIN / ASHFORTH family GEDCOM and is created using Personal Ancestral File (PAF). In order to facilitate research, data is presented in several different formats using various software applications and scripts.