Facebook has included a new and exciting feature which allows users to download Facebook account information including messages, wall posts, comments, photos, videos etc. in a zip file format which could be saved on personal systems for offline access.
Here is the how to
Login to Facebook with your username and password
Navigate to Account > Account Settings
Under Settings tab click Learn more button followed by Download your information option
On next screen click Download button to continue, there you will find the information about what kind of data could be grabbed from Facebook account
Then proceed with another Download > Okay button
Now, Facebook will create a link of ZIP file with all information related to your Facebook account and you will receive an email to your Facebook associated email address which contains the download link of your Facebook account information.