Its really that Easy!! if you are looking for a quick solution from word press itself to back up your blog , this is it !! It will save you hours of heartache later if something goes wrong, But there are much more detailed back up options available as well if you want.
Simple wordpress export backup in xml file
The quickest way to back up your wordpress blog is to use the export function in wordpress admin panel itself, under the tools section. Check the pic below
Be warned though it only back ups on post, pages and comments and does not back up the photos. You can also do a Ftp back up of the images folder to complement this.
I wouldn’t recommend this backup options if your blog has big/many posts. I you try to back up your blog with the export feature and you have many post you can end up with a xml file bigger than 10Mb.
Get the WordPress Database Backup plugin for a more detailed backup
A more detailed backup can be done using the WordPress Database Backup plugin shown above and below also in pic. This plug-in is pretty good as you can either choose to back up the database to your computer ( no messing around in cpanel or hosting login) or schedule a backup to be sent regularly to email as well.
Here are some more links for wordpress database back up