words - What's the difference between 治す{なおす} and 治る{なおる}?

My dictionary says they are both cure/fix, so I am wondering what the difference is and how to use them?

Is it an active/passive difference, or transitive/intransitive? Or just a subtle nuance? I couldn't find a good example of usage.

I found this question, but it just refers to the different kanji, not the different words.

Thanks

Answer

治す is transitive.

傷を治す
to heal a wound

ほとんどの病気は薬を使わずに治すことができる。
Most ailments can be cured without medicine.

治る is intransitive.

風邪が治った
my cold got better

傷が治らないので、私はまた病院に行った。
My wound did not heal, so I visited the hospital again.