Sorry for being harsh, but on day 2 of your Perl journey it is a waste of time to examine why some function was deprecated.

You can read about the operators & at Bitwise And and about ^ at Bitwise Exclusive Or, both in perlop. The same document also has a section on Bitwise String Operators which explains some of the caveats, and if you really, really want to know you can consult perldeprecation to learn more about what has been deprecated.