Why are some hashes initialized using curly braces, and some with parentheses?

Question

I\'m looking at the following code demonstrating nested hashes:

my %HoH = (
    flintstones => {
        husband   => \"fred\",
        pal       => \"b         


        

Answer 1

The essential difference (....) is used to create a hash. {....} is used to create a hash reference

my %hash  = ( a => 1 , b => 2 ) ;
my $hash_ref  = { a => 1 , b => 2 } ;

In a bit more detail - {....} makes an anonymous hash and returns a reference to it wich is asigned to the scalar $hash_ref

edited to give a bit more detail