In 2002 a college student named Matt Mullenweg installed the b2 or cafelog blogging system for personal use. On April 1st, 2003, Matt created a new branch of b2 on SourceForge by forking the original b2/cafelog system to create his own version with the help of Mike Little. Matt’s friend, Christine Tremoulet recommended calling it WordPress and that’s the name they stuck with.
With WordPress.org, you host your own site (we recommend this). You’ll purchase your own web hosting service and then you’ll install the WordPress software on that hosting.
With WordPress.com, on the other hand, it’s WordPress.com that takes care of all of this for you (easier to start, less freedom). You just register for an account and you can start building.
WordPress.org is for website owners who want to be independent, e.g., SEO users, ecommerce stores / online stores. Using WordPress.org means that you build everything on your own from the ground up. WordPress.com is good for you if you don’t want to get your hands dirty with hosting, third-party tools, and installing custom website functionality by hand. You just sign up and get an online space of your own instantly.