7 ms·The guy's name being John, but his nickname being "Jack", always confuses me.by avree 1y agoThe guy's name being John, but his nickname being "Jack", always confuses me.jjice 1y agoDon't quote me on this, but I believe that Jack is a pretty common nickname for John, at least based on the John/Jacks I've met in my life.avree 1y agoWow, TIL! Thanks - I googled it and you are right. I never knew they were related.