Facebook is Very Popular Social Networking Website Nowdays. It Also allow Users to Upload Videos and to share Videos with thier Freinds. But Facebook Only Allow Users to Watch Videos Online, there is no Option on Facebook to Download Video.
Here is Very Simple Trick to Download Video from Facebook. With this Trick you can Download Video from Facebook in MP4 Format
Below are the Steps to Download Facebook Video:
Step 1: Open Facebook Video you want to Download, In Adress Bar you can
Find Facebook Video Link. It Look Like:

Copy the Facebook Video Link
Step 2: Now Open this Website -> DownVids.Net
and Paste Video Url in Download Box Like this

and Click Download Button
Step 3: Then “Download this Video” Button Will be Appear there, Right Click on that Button
and Click on Save as, then Select Location to Download Video
Wait for Some Seconds and it Will Start Downloading your Video