WordPress is broken into two parts depending upon how you want to use it. They are commonly referred to as WordPress.Org or WordPress.Com. In reality, you will use the same software, it is just how you host and manage the software that changes.
WordPress.Org
WordPress.Org allows you to download WordPress to your local machine, or any web server of your choice, provided it meets the WordPress requirements. It also provides documentation, online help, and a way to search for free themes and plugins.
With WordPress.Org, you must use your own hosting service. You can host it internally on a server in your network, or even your own machine using something like WAMP, or MAMP. Internally focused websites are often referred to as Intranets, and I’ve set up numerous Intranet websites using WordPress over the years.
Or you can be Internet facing, using a hosting site of your choice, such as Host Gator, or one of the many others out there.
When you self host, you will be responsible for installing your own updates, backups, etc. Luckily there are a lot of plugins out there to help you with this.
WordPress.Com
WordPress.Com provides you with a free account and hosting for your WordPress website. The hosting, and other services, are provided by Automatic (they oversee WordPress development), and they have different levels of hosting.
Automatic currently offers three different levels of paid subscriptions.
Their free tier and the lowest cost “Personal” tier have the most limitations, including limiting the number of themes and plugins you can install to ones they have selected. With each tier increase, comes a price increase, but also more features. You can find out more at https://wordpress.com/pricing/. The highest tier allows you the same flexibly as if you hosted it yourself, on your own server, but the others come with limitations that you need to be aware of.
They also have a VIP service which can run several thousand dollars per month, but that is designed for large clients who get millions of visitors a day. (https://vip.wordpress.com/) Some fairly large websites use their VIP service, but it is usually too much for most websites.
WordPress.Com vs. WordPress.Org was originally found on Access 2 Learn