I couldn't understand the purpose of the bless function

Normally, if you have a hash reference:

my $hash = {
     a => 1,
     b => 2
};
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you can write:

say $hash->{a};
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but you cannot use a hash reference to call a function, e.g.

$hash->some_func()
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If you look at the code that creates a class, the new() function creates a variable called $self and assigns it a reference to a hash. bless() makes it so that you can use the hash reference to call functions.

An object is different from any other data type in Perl in one and only one way: you may dereference it using not merely string or numeric subscripts with simple arrays and hashes...

$aref->[0]

$href->{'a'}

...but with named subroutine calls...

$href->some_func()

In a word, with methods.

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