Steve,
A landing page is simply a page in your site network where a target customer "lands on" ...
Generally, an effective landing page is integrated with scientific principles of persuasion that can successfully compel your target customers to do what you want them to do, such as:
• Grab their attention, keep them interested in viewing more of your content, entice them to actively engage with your content, make them think and feel that they want and need more of your content, and compel them to do whatever you want them to do — Sounds like some sort of mind control, huh?
• Educate, inform and entertain them, enough for them to do other things that you want them to do ...
• Give their first names, emails, phone / mobile numbers and other details so as to grab your opt-in offer ...
• Buy and keep on buying whatever your selling ...
• Share and recommend your content to their peers ...
• Talk and say good things about your brand, your website, your content and everything else about your business in various online and offline places where they spend time in ...
That's it for now. Cheers!