First, the usual history.PAF is derived from an early version of Ancestral Quest.When the two split, Ancestral Quest would import PAF data, but would only save to its own format.
When FamilySearch decided to move the Ancestral File and Pedigree Resource File to a web base, they tied PAF to the web based operation and invited other genealogy programs to become affiliates.
At that point AQ modified their data saving to allow either their own format, or you could keep the PAF format to maintain your connection through PAF to the web based portion.
Other programs have joined the affiliate program but I don't think they allow you to keep your PAF format file.Here's the link to the various programs certified by FamilySearch:
You'll need to check the entry for whatever program you're interested in to see whether you can keep your PAF based file without converting.
As a handy bonus, if you use AQ and keep things in your PAF based files, you can still use PAF Companion, which is less expensive than the Charting Companion versions made by Progeny for other genealogy programs.