Sometimes abbreviated as LC, lowercase is a typeface of small characters. For example, a, b, and c is lowercase and A, B, and C is uppercase. As long as the Shift key is not being pressed and the Caps lock is not active everything typed is in lowercase.
Using the lc command
my $example = "HELLO WORLD";
$example = lc($example);
In the above example, the $example variable is first set as all lowercase. The second line makes the text all lower case.