A few language questions.. [PHP, PERL, Javascript, etc]

So, lately I have been getting into the whole MySQL and PHP language pretty deeply. Today my web design teacher handed me a few books with nothing in them on php, but instead, perl and asp. I was wondering are those longuages any better than PHP… Is it advisable for me to maybe take a look at them? Are there things I can do with those two languages that PHP can not.

I was also wondering something about javascript.

Is it still used often today? And what it is used for, is it anything that PHP, PERL, or ASP can not do?

Thanks, any input is greatly appreciated :D:D