GEDCOM was created in 1984.

A GEDCOM file is a file format for genealogy data. As this is a text file, you can in principle create a GEDCOM file using any text editor. However, it is better to create one using a genealogy software package. There are several open source genealogy software packages that work with GEDCOM, e.g. GenealogyJ and GeneoTree. Please see the related link below for more details.

It's not possible to see someone else's GEDCOM upload, unless all the profiles created from that GEDCOM are public, or the Profile Manager has added you to the Trusted List for all the profiles.

Here are two random examples of GEDCOM-created profiles: http://www.wikitree.com/wiki/Aadland-12

http://www.wikitree.com/wiki/Zwicker-63

There are many desktop application programs that will run GEDCOM files. However, this question asks if one or some of these programs are know to work better than others with GEDCOM files created by the WikiTree online program. This question assumes there is no personal, desktop version of WikiTree.

GEDCOM is the standard format for import / export of family trees. Check the link for the import facility for wikitree.