OK, that title is just me being facetious. But seriously, I cannot be the only one who is sick of their Facebook feed being filled with "1 Like = 1 RIP", "Like if you think this sick kid deserves a BMX", "Like = You Care, Keep Scrolling = You're a total b@st@rd", "Ignore this if you hate puppies", "This kid asked Santa for his Dad to come home from Iraq, like if you want to see them reunited", "Like if you hate cancer", etc, etc, etc.
I'm going to just come right out and say it. If you are on my friends list, I am automatically going to assume that you hate cancer. In fact, if you are human, I'm going to assume that you hate cancer. That's not fair, actually, I'm going to assume that even the dogs and cat on my FB friends list would hate cancer if they had any concept of what it is. You don't need to like a photograph. I'm going to assume that you are basically a moral, upstanding human being (despite some trying desperately to convince me otherwise). I presume you want the kid to get his Dad home from Iraq, that you love puppies (or at least don't hate them), think all the sick kids should have bicycles, wish everyone who deserves it to rest in peace, and respect war veterans and old people in general.
Liking a picture will not cure cancer. It will not make the girl get naked, or the little boy fall down the well, or the snake eat the giraffe, or the hysterical/scary/amazing thing happen. What it will do is raise the likes on the photograph/page, which will probably then be sold on by the unscrupulous person/group who set it up to trick people into clicking on heart-rending/intriguing/gross links to make them more money.
Basically, the more people who like/share a picture (or profile) on Facebook, the more exposure the page/profile the picture belongs to gets, and the more valuable that page/profile becomes. The login for the page/profile is then sold to a company for a massive profit (bearing in mind all Facebook pages are free to create, pretty much a 100% profit), the company change the details of the profile or page to their own, and suddenly the business has a page with 50,000 likes . . . Instant popularity!
A page's "Edge Rank" is the score it is given which controls how the page interacts with other pages/profiles. The higher your ER the more your page is shown on newsfeeds, etc. Facebook decides which ERs are relevant to each person (hence the reason some days your feed is just chock-full of rubbish).
So be careful what you click on. If necessary, Google the name of that sick little kid or brave soldier. If it's a real story, chances are it has a real page that won't be raising money for con-artists.