Difference between WordPress.org and .com
WordPress.org – is where the software “WordPress”available free of cost to the public, which goes the same to thousands of themes and plugins. You will need a pay for domain names and web host to host your WordPress site.
WordPress.com – on the other hand, takes care of all of the hosting for you. You don’t have to download software, pay for hosting, or manage a web server. They offer a variety of themes and plugins; however, you will not be able to modify the code for your website, upload custom plugins nor themes.