what facebook means by number of people saw this post?

[Manish]

I have started advertising my facebook page through ads and after getting 30 likes it is now showing me stats about how many people saw my post, i am little confused in this, what does facebook means when it says 3 people saw my post, does it mean it was on top position for that much people or even if the post went somewhere at bottom then also it will count it as visibility, because as much my coding knowledge is concerned i dont think there is any method by which php script can track scrolling of page, it can count on the number of times a page is loaded, please guide me.

[Daniel]

That Is The Number of People That Saw And Read your Post That you Posted