Back in January 2013, I wrote about this when we were calling them Facebook's Hidden Messages but they are now called Other Messages.
When you click on your Messages tab in the left hand sidebar of the Home page of your personal profile, you will see the two options.
Each will have a number of messages in brackets and it is quite alarming to discover how many messages go into that Other folder.
Facebook's Other Inbox
So how does it work? Well, if you try to message someone on Facebook to whom you are not connected, Facebook puts that message into their Other folder.
It's great because you find a lot of the messages from those strange people who try to chat you up on Facebook in there. When I checked today, one chap had sent me three over the course of 8 months. His most recent was imploring me not to ignore him! Maybe I should switch my profile visibility to a more private option.
At the end of 2012, Facebook began trialling an option where you could pay to have your message put into the inbox of people that you didn't know. This rolled out to everyone in the middle of 2013.
So now, if you try to message someone and there is no mutual friend, you will be asked to pay a fee to guarantee that it goes into their inbox.
I believe it costs 66p per message for normal people - down from 79p last year. For celebs, it can be as much as £10 - that was an example which was being quoted to send a message to the main Inbox of Tom Daley, the diver last year.
There is also a filter option.
You can either select the recommended Basic option where you will 'Mostly see messages from friends or people you may know' so that would include Friends of Friends but anyone else will be consigned to Other - the equivalent of a spam filter.
Or you can choose the Strict Filtering option which will mean that you will see communications from 'Mostly see messages from friends. Messages from people you want to hear from may go to your Other folder.' This means that people you may actually want to hear from could be dumped into Other and, unless you remember to check it regularly, important notices might not be seen.
As Facebook admit, they do sometimes get it wrong - you may get messages in your Inbox that are from the friend of a friend who is messaging a group of mutual friends or a member of a group you're in who messages you might end up in. You could also hear from a friend who isn't on Facebook and uses your contact info to send you a message via the Facebook Messenger app (more on that in the future).
When filters won't make any difference - 'Paid' Messaging
And, of course, the real one that makes you sit up and take notice - messages may appear in your Inbox from people to whom you are not connected on Facebook but who have paid to ensure that their message is routed to your Inbox rather than your Other folder.
Well, that sounds as if businesses are going to be able to pay to put stuff into your Inbox...?
Isn't that what we might call spamming? It remains to be seen if Facebook will roll this option out to businesses in the future.
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