01 Overview

Perl source code is simply lines of text (a script) which the perl . exe program
executes one by one, starting from the top .

Perl has a very loose formatting requirement
- freespace to left of statement is ignored - indent all you want
- freespace anywhere except in string literals is ignored
- end all statements in semicolon ;
- anything on a line after a # is ignored - is a comment
- Perl executes top to bottom
- sub routines can be placed anywhere within the code - convention is at bottom
- sub routines can be referenced before they appear
- Perl is case sensitive
- () parenthesis, when normally used, are optional
- term "escape" is means to prevent character from being interpolated within quotes

Data types
$    scalar (numbers and strings)
@   arrays
%   associative arrays
&   Subroutines