How should I use the “my” keyword in Perl?

Question

I keep seeing the \"my\" keyword in front of variable names in example Perl scripts online but I have no idea what it means. I tried reading the manual pages and other site

Answer 1

Quick summary: my creates a new variable, local temporarily amends the value of a variable

In the example below, $::a refers to $a in the 'global' namespace.

$a = 3.14159;
{
  my $a = 3;
  print "In block, \$a = $a\n";
  print "In block, \$::a = $::a\n";
}
print "Outside block, \$a = $a\n";
print "Outside block, \$::a = $::a\n";

# This outputs
In block, $a = 3
In block, $::a = 3.14159
Outside block, $a = 3.14159
Outside block, $::a = 3.14159

ie, local temporarily changes the value of the variable, but only within the scope it exists in.

Source: http://www.perlmonks.org/?node_id=94007

Update

About difference between our and my please see

• What is the difference between my and our in Perl?

(Thanks to ThisSuitIsBlackNot).