What's the difference between normal fixer and fix with hardener?

I was just curious about this what is the diference between normal

black and white rapid fix and a fixer with hardener? Is one better

than the other? Thanks for putting my curiosity to rest.

There are various 'hardeners' used in fixer. Kodak Rapid Fixer, for example, provides a separate bottle of hardener that is primarily dilute sulfuric acid. The extra acid 'pickles' the gelatin (sort of like tanning leather) to make it tougher and less susceptible to scratches.

I use rapid fixer with the hardener for film, but some people don't like it for prints because the toughened emulsion won't accept toning or retouching as easily.

It's certainly reasonable to use fix either with or without hardener, depending on your intent. The 'fixing' itself (removing the undeveloped silver) isn't much affected by the hardener.