WordPress is generally regarded as being pretty awesome for building websites straight out-of-the-box - and it is! But - and its a big but - its built-in capabilities "out-of-the-box" are pretty limited - for instance there's no contact form, only limited image manipulation and no e-commerce capabilities.
All those additional functionalities (and many, many more) are handled by plugins. Plugins come in many different flavors and if you ask 100 WP developers for their favorite or essential plugin you'll likely get 100 different answers!
Pam and I plus our good friend Don Seckler from Peak Inbound Marketing are going to make our own lists of our essential/favorite plugins and then we'll present our top 10-15 essential/favorite plugins at the meetup and give a bit of background on what they do and why they might be important to you and your website.
This should be a good learning session for both beginners and seasoned WP users who are looking to move beyond the basics of what WP has to offer and learn how professional WP implementors add important functionality to their client's websites.