The y/// Operator is used to transliterate string.

     y/search list/replace list/options;

In the above syntax, "search list" is the string to be searched for, "replace list" is the string to be replaced, "options" are optional arguments.

    #! C:\programfiles\perl\bin\perl
    print "content-type: text/html\n\n";
    $string = 'maurice mike is the father of morris mike';
    $string =~ y/abcde/ABCDE/;
    print $string;

     mAuriCE mikE is thE fAthEr of morris mikE

In the above y/// Operator for transliterate string example the smaller case string "abcde" is replaced with uppercase "ABCDE" in the string.