When we use hash functions, we take our input and transform it into an output, which is in a fixed size length. When we are using mt five, it's 128 bit value. When we're using Sha one, it's 160 bit, and so on up until 512 bit Sha 512. So let's give it a try. Let's use the echo command to output this text string in corruption. And let's grab it using open SSL.

For the first hash function, we'll use MD five. All right, now we'll use Sha one 168 Great shot 256 bit, it's a longer value much harder to guess, and Sha 512. Now if you've watched my previous course you remember that a certificate authority takes a certificate hashes it to make a signature out of it and then encrypts it using its own private key. So let's take a look at a certificate and see which hash function is being used to create a signature. Let's move over to the key chain the place where Apple keeps all these certificates. And let's see the Amazon root certificate and Amazon is using a Sha 256 to create the signature