The difference between Random Critical Rate and Random Critical Probability

Yo,

I am just in need of a detailed explaination for this simple question. Examples would be the perfect way. It's been bothering me way for too long.

Le me give my thanks in advance.

The random critical rate increase the chance of doing extra damage on a critical and random crit probability is the chance of doing the critical with the extra damage.

What I said is only based on my opinion so I can be wrong or right idk.