Facebook has hit the headlines in recent weeks over its handling of your private data, and now the shocking extent of information held by Google has been revealed.
In a series of tweets, one IT expert has laid out exactly what the search giant knows about him, dating back to 2008, which he describes as 'preposterous'.
It ranges from every place he visited in the past year to every website he clicked on, and even contained files deleted from his Google Drive cloud storage account.
The news comes in the wake of the Cambridge Analytica scandal, which saw a Trump-affiliated firm obtaining data on 50 million unsuspecting Facebook users.
This information was used to target voters in the US, based on psychological profiling, with political adverts spreading disinformation.
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Facebook has hit the headlines in recent weeks over its handling of your private data, with CEO Mark Zuckerberg (right) in the firing line. Now the shocking extent of information held by Google, headed by Sundar Pichai (left) has been revealed
Web developer Dylan Curran, based in Waterford, Ireland, decided to download both his Facebook and Google archives on Saturday.
The data held by the world's most popular social media site was fairly large, at around 600mb, equivalent to roughly 400,000 Word documents.
But this paled in comparison to Google's data file, which was 5.5gb, almost ten times larger. This is around the same size as three million Word documents.
Sharing his findings on Twitter, in a post retweed more than 150,000 times, he said: 'Want to freak yourself out? I'm gonna show just how much of your information the likes of Facebook and Google store about you without you even realising it.'
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Mr Curran found that Google was constantly tracking his location in the background, including how long it took to travel between various points.
It also held details about his hobbies and interests, as well as guesses on his possible weight and income.
Speaking to NBC News, he said: 'It's wrong to trust any entity that big with so much information.
'They're just trying to make money,' and at some point, 'someone is going to make a mistake.'
Dylan Curran decided to download both his Facebook and Google archives. Facebook's 600mb, equivalent to roughly 400,000 Word documents, paled in comparison to Google's data file, which was 5.5gb, around the same size as three million Word documents (stock)
Where you've been
If you have location tracking turned on via your smartphone, tablet or other connected device and they're switched on, Google stores details of everywhere you've been.
For Mr Curran, this included his travels around Ireland over the previous 12 months, including journey times between towns and cities.
When MailOnline decided to drill down into this data, it revealed a surprising level of detail.
As well as foreign travel, it included the name of a number of pubs visited, the length of time spent in them, and the route taken to get home.
To find out what data Google stores on your travels, click here.
If you have location tracking turned on via your Android smartphone, tablet or other connected device, Google stores details of everywhere you've been. For Mr Curran, this included his travels around Ireland over the previous 12 months
Events you've attended
Google's data files contain a complete record of your Google Calendar.
This is broken down into all the events you've ever added, whether you actually attended them, based on your location, and what time you attended.
Mr Curran shared a section that shows him going for an interview for a job in marketing, including the time he arrived.
To access your Calendar history, as well as your complete Google data file, you need to request your Google Takeout file by clicking here.
Be aware that, if your file is anything like Mr Curran's, this may take a long time to download.
Google's data files containing a complete record of your Google Calendar. Mr Curran shared a section this shows him going for an interview for a Marketing job, including the time he arrived
WHAT IS THE CAMBRIDGE ANALYTICA SCANDAL?
Communications firms Cambridge Analytica has offices in London, New York, Washington, as well as Brazil and Malaysia.
The company boasts it can 'find your voters and move them to action' through data-driven campaigns and a team that includes data scientists and behavioural psychologists.
'Within the United States alone, we have played a pivotal role in winning presidential races as well as congressional and state elections,' with data on more than 230 million American voters, Cambridge Analytica claims on its website.
The company profited from a feature that meant apps could ask for permission to access your own data as well as the data of all your Facebook friends.
The data firm suspended its chief executive, Alexander Nix (pictured), after recordings emerged of him making a series of controversial claims, including boasts that Cambridge Analytica had a pivotal role in the election of Donald Trump
This meant the company was able to mine the information of 55 million Facebook users even though just 270,000 people gave them permission to do so.
This was designed to help them create software that can predict and influence voters' choices at the ballot box.
The data firm suspended its chief executive, Alexander Nix, after recordings emerged of him making a series of controversial claims, including boasts that Cambridge Analytica had a pivotal role in the election of Donald Trump.
This information is said to have been used to help the Brexit campaign in the UK.
Everything you’ve ever searched for
Google, somewhat unsurprisingly for a search engine, records everything you search for on the internet.
What might shock you, however, is that this is kept on file even when you delete your history.
Mr Curran's log contained 90,000 different entries, even showing images he downloaded and websites he accessed.
This included banned torrent site ThePirateBay, which he mentions in his tweets to illustrate how much damage this information could do if it becomes public.
Google records everything you search for on the internet, which is kept even when you delete your history. Mr Curran's log contained 90,000 different entries, including accessing banned torrent site ThePirateBay
Google stores search history across all your devices on a separate database.
That means, even if you delete your search history and phone history, the search giant still has your entire history.
To delete it permanently, you have to manually access the My Activity log here and delete everything.
This will need to be done for all devices individually.
Ad topics that might interest you
Google builds a marketing profile on you, based on a number of factors.
These include details like your location, gender and age.
It also includes your hobbies and both your personal and professional interests, as revealed through your searches and web activity.
Google builds a marketing profile on you, based on a number of factors. These include details like your location, gender and age, as well as your hobbies and interests. Some of these seem to have been logged by a single search or website interaction alone
In the case of Mr Curran, this also included guesses about his relationship status, weight and income.
When MailOnline checked this, we found a range of interests, some of which seem to have been logged by a single search or website interaction alone.
To access your ad profile, click here.
Information you deleted and emails you sent
The Google Takeout file also includes a record of all of the information you've uploaded to your Google Drive account.
In Mr Curran's, he found files he had already deleted, including past resumes and monthly budgets.
The Google Takeout file also includes a record of all of the information you've uploaded to your Google Drive account. In Mr Curran's, he found files he had already deleted, including past resumes and monthly budgets
Every e-mail Mr Curran ever sent or received, including deleted and spam messages, was also recorded
He also found all the computer coding files and websites he'd ever made, as well as his PGP private encryption key, which had been deleted, used to protect his e-mails.
Every e-mail Mr Curran ever sent or received, including deleted and spam messages, was also recorded.
To find out what files Google has from your Drive account and email, download your Takeout file here.
The apps you've used
Google holds information on all the apps and browser extensions you use.
This includes how often you use them, where you use them, and who you interact with through them.
This can include details like who you talk to on Facebook, what countries they are in and even when you go to sleep.
To find out what information Google has on the apps you use, click here.
Google holds information on all the apps and browser extensions you use. This includes, how often you use them, where you use them, and who you interact with through them
Your YouTube history
Google knows all of your YouTube browsing history.
This can reveal a multitude of personal details about you, ranging from your political and religious beliefs, to mental and physical health issues.
In Mr Curran's case, it revealed every YouTube video he'd ever searched for or viewed, since 2008.
To check your YouTube history file, click here.
Google knows all of your YouTube browsing history. This can reveal a multitude of personal details about you, ranging from your political and religious beliefs, to mental and physical health issues. In Mr Curran's case, the log went as far back as 2008
When you worked out
If you use Google Fit, the firm also keeps records on every time you workout.
In Mr Curran's case, this included all the steps he'd ever taken, every time he'd walked anywhere, as well as running and cycling.
It also included all the times he'd recorded meditation and yoga sessions.
Mr Curran has since deleted this information and revoked Google Fit's permissions.
If you use Google Fit, download your Takeout file to access your records here.
If you use Google Fit, the firm also keeps records on every time you workout or meditate. In Mr Curran's case, this included all the steps he'd ever taken, every time he'd walked anywhere, as well as running and cycling
WHAT HAS FACEBOOK DONE TO ADDRESS PRIVACY CONCERNS?
Facebook is giving its privacy tools a makeover as it reels from criticisms over its data practices and faces tighter European regulations in the coming months.
The changes won't affect Facebook's privacy policies or the types of data it gathers about its users.
But the company hopes its 2.2 billion users will have an easier time navigating its complex and often confusing privacy and security settings.
Facebook is giving its privacy tools a makeover as it reels from criticisms over its data practices and faces tighter European regulations in the coming months. This image shows how the settings will appear before (left) and after (right) the redesign
Facebook says it's trying to make the controls easier to find and to give users a simpler way to access and download the data it collects on them.
The announcement follows revelations that Trump-affiliated consulting firm got data on millions of unsuspecting Facebook users.
Facebook is also facing criticism for collecting years of data on call and text histories from Android users.
In a written statement, Erin Egan, vice president and chief privacy officer, policy, and Ashlie Beringer, vice president and deputy general counsel, said: 'Last week showed how much more work we need to do to enforce our policies and help people understand how Facebook works and the choices they have over their data.
This image shows a redesign of Facebook's privacy tools. The changes won't affect Facebook's privacy policies or the types of data it gathers on users, but the company hopes users will have an easier time navigating its complex settings menus
Among the changes, Facebook is making data settings and tools easier to find, is introducing a new privacy shortcuts menu, and is adding tools to find, download and delete your Facebook data
'We’ve heard loud and clear that privacy settings and other important tools are too hard to find and that we must do more to keep people informed.
'We’re taking additional steps in the coming weeks to put people more in control of their privacy.
'Most of these updates have been in the works for some time, but the events of the past several days underscore their importance.'
Among the changes, Facebook is making data settings and tools easier to find, is introducing a new privacy shortcuts menu, and is adding tools to find, download and delete your Facebook data.
All of the photos you've ever taken or searched for
Mr Curran's Takeout file includes details of all of the photos he's ever taken with his phone.
This was broken down by year and includes metadata on when and where he captured the images.
It also included every picture he'd ever searched for or saved.
This included every location he's ever searched for or clicked on, every news article he's ever searched for or read, and every google search he'd made since 2009.
To check your image history, download your Takeout file here.
Mr Curran's Takeout file includes details of all of the photos he's ever taken with his phone. This was broken down by year and includes metadata of when and where he captured the images
It also included every picture he'd ever searched for and saved. This included every location he's ever searched for or clicked on, every news article he's ever searched for or read, and every google search he'd made since 2009