This is used for 56 bit DES encryption,its a one way hash function. In the function plain text and salt is converted into a digest. Small changes made to the plain text or salt will have a large change in digest.

  crypt (plaintext, salt)

In the above syntax, this function takes two arguments first argument is "plaintext", second one is the "salt" value.

    #! C:\programfiles\perl\bin\perl
    print "content-type: text/html\n\n";
    $string = "ABV.PNT4TtMZQ";
    $string2 = "Hioxindia";
    $temp = crypt($string,'AB');
    if ($string=$string2)
     {
      print "Crypt Matches";
     }
    else
     {
      print "Crypt Dont Match";
     }

     Crypt Matches

In the above example already a string "Hioxindia", with the salt AB is encrypted and the digest is stored in "$string", then the same string "Hioxindia" and salt is explicitly encrypted.It displays an "Crypt Matches".