Socrates440:

Have you read perldoc perlre? (See what I did there? The Socratic method in action!)

Seriously, though, after the close of a regular expression, you can give it flags for things like case (i)nsensitive matching, as described in the aforementioned document.

As for the questions regarding the second statement, perlre answers those as well.

...roboticus

When your only tool is a hammer, all problems look like your thumb.