WordPress allows you to both host your site directly on wordpress.com and/or use WordPress purely as the software powering your website that’s hosted on your own domain.
Before you begin
We recommend backing up your site before making any changes or updates. That way you’ll have a copy of it to restore if necessary.
If you’re not sure how to backup your WordPress site, follow the WordPress backup documentation. If you find it difficult, seek support within the WordPress support forums or browse for help in our own webmaster support community.
Full Guide: WordPress — Webmaster’s Mobile Guide.