I am a Mac user myself, but the GEDCOM "standard" makes that irrelevant. It serves like RTF (rich text format) to expedit cross platform database exchanges. But "standard" is something that needs to be understood as in quotes. You don't need to know much about the innards of how it works, but here is a complete explanation if you want it.
I can't list everything here, just a few that I either use now or have used. There are some pointers at the bottom to software lists maintained by others. I use Reunion and recommend it with enthusiasm to Mac users.
Software to create and maintain Family Tree databases
- Reunion (Macintosh, commercial)
- GEDitCOM (Macintosh, commercial)
- HEREDIS (Macintosh, commercial)
- PAF for Macintosh (Personal Ancestor File, from LDS's FamilySearch.Org - was free, but now defunct)
- Personal Ancestry Writer The Mac version of PAF is obsolete, but this is a free extension developed by a private individual
- phpGedView (Mac OS X, Apache PHP, free Open Source)
- Family Tree Maker (Windows, commercial; Mac version too, but old)
- Legacy (Windows, commercial)
- Personal Ancestor File (Windows and Mac, free)
- Family Tree Legends (Windows, commercial) "Smart Matches" (GenCircles) seems a very useful concept, alas no Mac version.
- HEREDIS (Windows & Macintosh, commercial)
Software to convert GED files to web pages
- GENDEX, a GED2HTML source and archives
- GED2WWW, another program to convert GED files to web pages
- GED page maker (GedPage)
- IGM (perl - UNIX)
Software to remove "personal information" (for living persons) from GED files
Links to more software