Exporting your WordPress data (posts, pages, custom post types, comments, custom fields, categories, tags, custom taxonomies, and users) is sometimes necessary and useful. If you are moving to a new host or just want a backup of your site data, then Exporting your site is the answer. Once the Export file is created, that file can be used for import by the Tools Import SubPanel.
The Tools Export SubPanel is quite simple–just specify the desired Filters, if any, you wish to apply, and then click the Download Export File button to save that file to your local comuter.
When you click the Download Export File button, WordPress will create an XML file for you to save to your computer.
This format, which is called and WordPress eXtended RSS or WXR file, will contain your posts, pages, custom post types, comments, custom fields, categories, tags, custom taxonomies, and users.
Full list importing content: