Variables  Using Associative Arrays

• An associative list or hash table is useful for storing name-value pairs
• A hash table variable is designated by the "%" prefix.  
• There are many ways to initialize a hash table variable:  

1. Initialize the hash as a list:  %days = ( 'M', 'Monday', 'T', 'Tuesday' );
2. We can initialize the hash table element-wise : $days{'W'} = 'Wednesday';

• Again, you can use any scalar data type for the key or for the value

        $myConst{"PI"} = 3.14159;
        $hg{42} = "life, the universe, and everything";
• Accessing a value from a hash is easy: print "$days{'T'}\n";  
  prints Tuesday to screen