What's Wordpress?

Sometimes I feel like I just can't keep up. Last night we had dinner with the 25-year-old grandson of my dad's friend. He brought his new iPad (not called the iPad 3 - just the new iPad... wonder what they end up calling the next new iPad... the new new iPad?! I know, off topic) and he was busy demonstrating the amazing screen resolution. I swear it looked practically 3-D. We got to talking and I asked him what he did for a living. He's internet marketing for the healthcare industry. He said he likes to dabble in creating websites. I asked what platform and he said "WordPress". I had never heard of it. From Wikipedia: "WordPress is a free and open souce blogging tool and content-management system (CMS) based on PHP and MySQL. It has many features including a plug-in architecture and a template system. WordPress is used by over 14.7% of Alexa Internet's top 1 million" websites and as of August 2011 manages 22% of all new websites. WordPress is currently the most popular CMS in use on the Internet."

Wondering if anyone out these is familiar with WordPress? Is anyone using it in the classroom?