The one major difference between WordPress.com and Wordpress.org is who is hosting your website.
WordPress.com takes care of all of the hostings for you.
On the other hand, With WordPress.org, YOU host your blog or website. WordPress.org is where you’ll find the free WordPress software that you can download and install on your web server.
It is the managed platform where you focus on your content, If you are using a wordpress.com for business purpose then it can be highly secured as versatile as self-hosted, it has premium hosting, security, and backups are included & in this you can also upgrade to a custom domain, and you can choose from hundreds of beautiful themes, then make it your own with Custom Design. Sharing functionality is included, You can also connect (Integrate) it to your social networking sites like Facebook, Twitter, Tumblr, Instagram, etc..and other social networks. And spread your business.it has popular features like sharing, stats, comments, and polls are included you can install plugins to extend your site’s capabilities e.g (to create your woo-commerce store)
A personal setup session live chat and email is also available in wordpress.com
You’ll need to find a host and perform backups wordpress.org offer vault press for security and backups in this, you need to install custom themes, build your themes with PHP and CSS
You need to install the plugin, like a jetpack, to enable sharing functionality on your site and visit the wordpress.org support forums for assistance, No registration with wordpress.org is required
You can download the WordPress software for free at https://wordpress.org, but it should be installed on a web server before it starts to work. You will need to research and install your themes and plugins for your hosting.