Scalars are variables or expressions that resolve to a single value, either a number, string, or a reference.

$n = 1;    # Integer
$n = 1.0;  # Floating point number
$n = 0100; # Beware: OCTAL! This assigns "8" to $n;
$n = 0xFF; # Hexadecimal: $n = 255;
 
$s = "string"; 
$s = 'string';  # Non-interpolated
 
$n = $s; # Another scalar. Datatypes change dynamically
$r = \@array; # A reference
 
print $variable; # To get value from a scalar.