Social networks store the data you have deleted.

Yesterday, the BBC published the results of the experiment at Cambridge University; it turned out that popular social networks store photos on the server after they are deleted by the user.
The experiment was conducted as follows in an unwise manner, on 16 social networking sites photos were uploaded, and direct links to them were saved; after they were deleted, the links continued to display images on 7th sites, including on Facebook.

“This confirms that social networks often adhere to a“ lazy approach ”to user privacy, preferring to act as simpler than not more correctly, says one of the authors of the experiment, Joseph Bonneau,“ But privacy protection must be stitched. ” in the service, and not act as a voluntary appendage. "
In the Contact, “deleted” photos are also not immediately deleted, this can be easily seen in a similar way.

As for the Facebook network, they commented on this by saying that the photos from their servers are removed immediately. “True, the URL of the files continues to respond for some time in the content network of the provider until they are corrected. This usually happens pretty quickly, ”a Facebook representative explained, but now it’s all the same for users of this social network, as recently new rules came into force under which users agree to transfer their data to the company for perpetual use, this caused a number of protests from users of this network.

With a high degree of probability, some resources can store all changes of users made by them, so I would advise to be more careful with this in a world where information rules all :).