When Facebook first started out, there were countless sharing scams that tricked users into thinking they could see who has been visiting their profile and browsing their photographs. "Click this link and find out who's been stalking you," the posts read which usually led its readers to some scam app that did nothing of the sort. While there is no app that shows you who visited your profile, Facebook undoubtedly knows everything that everyone does and there is a simple way to see if you have a potential FB stalker.

It is not as simple as "person X has recently viewed your profile," however, it is still fairly telling and a very good way to find out who's been lurking on your page. It all starts with the friends' photo box on your own timeline. While many people think the friends displayed in this box are random, the answer is much different.

Interactions on Facebook. Recently and over time. Recent interactions play a large role, especially if someone has recently viewed your profile page.

Profile views. They have viewed your profile and/or you have viewed their profile – Total amount of views when compared to other friends profiles viewed.

Tagged photos. Photos that you've been tagged in or have tagged your friends in.

Wall posts. Has this person posted on your wall recently, or you on theirs?

Likes. Have they liked your content or have you likes theirs?

Comments. On your posts or comments you've made on your friends' wall posts or pictures.

Photos viewed. They have viewed your pictures, and/or you have viewed theirs.

Currently online. Friends who are currently online or have recently been online. This typically applies for random people that might show up.

Messenger. Facebook messenger conversations between each other.

Mutual interactions. Between yourself and your friends will likely play a bigger role in determining who your "closer" 9 friends may be.

"Close Friends." If you've added friends to your "Close Friends" group, typically at least 2 of these people will be shown in the 9 friends box.

So, by process of elimination anyone can see if they have a stalker by narrowing down people who appear in their friends' box but do not meet any of the above criteria.