There are many fake profiles on social networks like Facebook and Twitter, as well as on popular online dating websites like Match.com. Facebook itself reported last year that there are 83 million fake accounts on its site. They make up a little less than 10 percent of Facebook's active monthly users, according to Gawker.
Most of these fake accounts are duplicate accounts--someone not realizing they already created another account or someone who has two accounts (one for personal reasons and one for professional reasons).
Twitter has over 500 million registered acounts, but CEO Dick Costolo said recently that about 140 million of those accounts are active. And there is actually a "Twitter undeground economy" where you can buy Twitter followers to make your profile look more popular. A study last year found that the average cost of buying 1,000 fake followers was about $18.
When you meet someone on-line and there's an emotional attachment. . . you can't very well just ask "are you fake or real". . . is there a way to verify the person's ID before meeting them?
For starters, if the photo looks like the person is a supermodel--it's probably a fake account.
If the person just seems too good to be true, she or he likely is.
Look at how many followers the person has. A fake account will have less than the average 130 users. They probably won't be interacting with other users on Facebook or Twitter.
In photos, see if the person is posing with other people. But then make sure those other people are tagged in the accounts and those people are actually active on FB as well.
But again, remember that one person can create multiple profiles and then have those accounts interact with each other.
Google the person. Make sure it all adds up.
You should also check if you can find out who the person's phone is registered to. There are many services that allow you to type in a number and do a reverse number look-up.
If you're really suspicious, hire a private investigator. Do this especially before you meet with someone in real life that you have doubts about. Meet that person in a public place and be sure that other people know where you are and who you are with.
Finally, if you have been duped, you should report it to both the social networks and authorities who will be able to more quickly shut down a profile than you would alone.
How do you protect your own FB pictures from being used like this without you knowing?
You can upload your own image to images.google.com and it will do a scan of all publicly available images to show where else your photo is being used. You can also find similar images so that if your photo was doctored, it would still likely turn up there. (See PDF for illustration of how to do this process).
Of course, Google can only search through publicly available webpages. If your photo is being used as someone else's Facebook profile photo, it would turn up in the search. But if your photo is being used as an additional photo on Facebook that's not viewable to the public, Google cannot find this photo.