State of NTFS Support at OSX 10.9.5 I acquired an external hard drive that came preformatted with NTFS. My MAC quietly mounted it read only. After some conversations with google, I discovered that MAC couldn't write NTFS by default, but actually did have the ability to write NTFS on Lion

I think Lion &lt; 10.9.5 

So is it possible to use this drive on 10.9.5 without reformatting ? And will it be possible to read the results on (currently existing) OS X variants >= El Capitan (=? 10.11.0) 

And if I do need to reformat, what's the least-likely-to-be-broken choice of file systems?

And if 10.9.5 can write to NTFS, how do I enable it? Will option 3 from http://www.howtogeek.com/236055/how-to-write-to-ntfs-drives-on-a-mac/ work on 10.9.5?
I have found these articles:

http://macdrug.com/free-ntfs-read-and-write-solutions-in-mac-os-x-el-capitan-or-older/

http://www.makeuseof.com/tag/write-ntfs-drives-el-capitan-free/

(pretty much identical)

If you want to reformat the external HDD I guess that the native Apple filesystem would be the most reliable choice, unless you have to use it with other devices... in this case I think FAT32 could be quite "universal".