The password hashes in the /etc/shadow file is usually divided into 3 groups seperated by the symbol $.
The first section, i.e. after the first $ symbol represents the hashing algorithm used.

The meanings of the different values in this field are:
$1 = MD5
$2 = Blowfish
$2a= eksblowfish
$5 = SHA-256
$6 = SHA-512

The next field, that contains a randomly generated or user defined string that works as the SALT to improve the password security.
For example, $thisisthesalt1234$ could be the SALT as well.

Now, the final section after the last $ sign is the encrypted password.

Example Password Hash:

$1$SFsdflQD$179ad45c6ce2cb97cf1029e212046e81

The given password hash is encrypted with MD5 and the SALT that was randomly generated was: SFsdflQD

And, 179ad45c6ce2cb97cf1029e212046e81 is the actual encrypted password.