UK printer supplies company Cartridge Discount seems to be developing quite a sideline in useful infographics for writers, and one of the latest is this one, distilling the craft of creating a screenplay into visual form, with a range of sources listed at the end of the graphic. And of course, you would be well advised to go and consult those sources before you start seriously working on the screenplay of your dreams, but at least this is a useful, and fun, jumping-off point.