I see two copies of my TT file, one that starts with a ~ , why is that and which is the correct one?

After starting my return, when I go back to the folder, there are two files, both the same size

2016 Albert D Form 1040 Individual Tax Return.tax2016 dated 12/27/16 3:14 pm and

~2016 Albert D Form 1040 Individual Tax Return.tax2016 dated 12/27/16 3:13 pm

Why is that? Which is the correct file?  If I always open the files from within the TT application, will I get the correct one?