Repository vs. Hosting
WordPress.org is a repository site that contains the open-source software for WordPress and makes it available to download for installation on a user’s personal domain. This provides better control and flexibility to the user when building their web site. The user will need to install the software themselves and then rely on their hosting service to provide the appropriate security, spam protection and backups/updates. Some of these functions are available at extra costs. Users will also need to keep up-to-date with the latest software releases from WordPress as updates on their personal web sites will be the user’s responsibility.
In addition to providing the software to download, .org also provides a library of documentation, support forums and training materials.
WordPress.com provides hosting for WordPress and, therefore, does not require the user to purchase a personal domain. Security, spam protection and backups/updates are automatically provided as part of the hosting package. Additionally, updates to the WordPress software will automatically be rolled in without any user interaction. WordPress.com is owned by Automattic and uses the open-source WordPress software.
Customization vs. Restrictive Use
WordPress.org contains a large suite of themes and plugins that may be downloaded and used on a user’s personal domain. These themes and plugins are fully customizable. Additional customizations include PHP and JQuery code.
As WordPress.com provides hosting, it is more restrictive and controlling. It provides a limited set of themes and plugins for use, although some premium themes are available for purchage. It does not provide the user with the ability to upload additional themes or plugin and prohibits its users from modifying any PHP.
When purchasing domain names from a service provider, users will have the ability to buy names (dependent on availability) that reflect their business and/or usage needs. WordPress.com’s hosted names all contain “wordpress.com”, which may not be appropriate for a user’s business and/or usage needs.
Let Me Sell You Something!
Users who pay for a hosting service for their personal domain(s) should expect to eliminate extraneous (3rd party) adverts on their web site. The hosting service is already making money by charging their users a hosting fee. Users are free to include any of their own 3rd party advertising within their web site.
WordPress.com provides a free hosting service and therefore makes its money by selling 3rd party adverting space on “your” web site. It is possible for a user to upgrade their WordPress.com web site to remove some of the adverts, but not all of them. Additionally, a user’s web site may not contain any embedded advertising due to contractual obligations with their 3rd party advertising, unless the user has bought a “Business” plan. WordPress.com provides a “Business” plan that will allow users to build eCommerce web sites on their (WordPress.com’s) web server.
Jetpack is a toolkit for WordPress, providing bundles of plugins to the WordPress users. When hosting a web site through WordPress.com, the Jetpack toolkit is already available. The basic features are available for free but there is an option to sign up for a paid plan and enhance the feature set: daily backups, premium themes and SCO tools.