Backing up your wordpress website takes 2 steps, backing up your database (where all of your posts and options are stored), and backing up your website (the “bones” or framework of the site):
How to back-up your database GoDaddy Support Page (outside link): http://support.godaddy.com/help/article/5648/backing-up-and-restoring-mysql-or-mssql-databases
How to back up your website files GoDaddy Support Page (outside link): http://support.godaddy.com/help/article/2992/backing-up-or-restoring-your-website