What does Facebook know about you? You may be surprised


With Facebook looming large in the news, everyone is wondering whether they were part of the Cambridge Analytic data set that is currently in focus. Whether or not you were involved in that particular incident, you’ll probably be amazed to learn just how much information you’ve given Facebook.

When users of the biggest social networking platform download or sign into the app that comes conveniently pre-installed on their mobile phones, they give permission for Facebook to access a wealth of personal data. While people may know this at one level (yes, it says the app can see contacts, calls, etc.) they don’t usually have a clear sense of what that data looks like in practice.

You can see the full picture, and here’s how. Be aware, though, that you may be shocked by what you find. Start by signing into Facebook on a desktop computer, not a mobile device. Go to the settings menu and click on ‘Download a copy of your data.’ Within a few minutes, you should receive an email from Facebook that contains a zip file with the data they’ve compiled.

Download the attachment and extract all the files. Now, you can see just what Facebook knows (and their clients, perhaps). Wondering who you’ve called over the years? Open the ‘index.htm’ file and click on the tab labeled ‘contact info.’ Creepy, right? And that’s only the beginning. The index file has tabs that will show you photos, messages, videos and plenty more. Dylan McKay has written a helpful Ruby script and shared it on github, so everyone can use it to make CSV files for easy viewing and summarizing of the files you get from Facebook.

You may also be interested to see the information in the ‘ads.htm’ tab. Advertisers certainly are. This file contains all the keywords used to target ads just for you – things they think will interest you and get a response. Like the friends Facebook suggests for you, the ads you see are based on information they glean from watching what you email and text about, who you talk to, what you search for and everything else you do online.

To be clear, this isn’t just about actions you took through Facebook; it’s the calls you made, pictures you took and everything else on your phone. You gave the company permission to see and use this information and guess what? They did!

If you have Facebook or Messenger on your phone, you’re giving up a lot more insight into your thoughts and actions than you may realize. And they’re not the only apps doing this, by any means. When you grant permissions to an app and wonder why they need access to your camera, for example, now you know.

They may or may not need that information to perform the app’s functions, but they do need it to learn what you say, what do and who you do it with, and to monetize that knowledge. Still feel like playing that cute game on your phone while chatting away in Messenger? Probably not…

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Sarah Warlick

Sarah Warlick founded Proof Positive Content to provide professional service firms with high-quality content that resonates with their target audiences. Sarah's writing appears in books, on the websites of over a dozen Top 100 Accounting Firms and in Accounting Today, Forbes and other leading publications, but usually under another name. Ghostwriters rarely get the glory - their clients do!