It is quite easy to back up and restore WordPress with the WordPress Importer plugin. First, back up your blog by going to your dashboard, and tools/import:

To restore your articles to another system, just select import and the WordPress:

Choose the file that you exported:

Assign the author as you wish. For us, we only have one author, admin. Check the box for downloads and attachments if you want those:

After the import, you will see a status page: