How to know the Facebook ID Number

To know the ID, see the link!
Example

http://www.facebook.com/profile.php?id=100001494699262

 The red letters is the ID!

If the ID doesn't appear in the link, e.g. http://www.facebook.com/ferdi.indonesia .

UPDATE : JUNE 12TH, 2O12

Well, to know the Facebook ID Number, e.g. your Facebook ID Number :

Click on your profile photo

If you use timeline on Facebook, you must right-click the photo, the Open In New Tab. Then, you'll found 3 IDs in the Address bar. Example :
http://www.facebook.com/photo.php?fbid=319283134798174&set=a.102076763185480.2877.100001494699262&type=1 
The blue letters is your ID!