Internet advertisements have become so invasive that everyone now has the awareness of being followed online. For example, just open Amazon, search for some products and then, even days later, see the advertising of that product.
Even more surprisingly, it may happen that after going to the shopping center, returning home, you can open any site and see an advertisement that reminds us of something of that center, perhaps not exactly targeted, but which still makes us feel like we had been followed.
These are personalized advertisements, which have become fundamental for all companies, but to which a limit has recently been set with the European law of the GDPR, which asks sites to warn about any personalized advertising present, with the option to disable it.
How do advertisements follow us everywhere and be personalized with such precision "> Guide to Cookies, who creates them, how to block or delete them
When you visit a website, it stores a cookie in your computer browser.
When you come back later, the cookie identifies itself and the site shows the products you were looking at previously.
In addition, if you subsequently visit a different site that hosts ads from the same advertising network, this also sees the cookie and displays the ads based on what you were watching previously, which is the so-called remarketing .
As for Google, what happens when you search for a product or website is that Google creates a user profile, even without knowing his name, by tracking his interests.
When you use your Google Account to access some other online service or application, the ads displayed will be based on this profile.
When you are connected to Facebook with the account stored on the browser and you visit a website that has installed the Facebook tracking pixel or even just the Like button, Facebook follows the user and when he returns to reading Facebook, the news will contain ads based on what you were watching previously.
One might think that by using the browser's incognito or private mode, which blocks the storage of ocokies, this fact of being followed by advertising can be stopped.
The advertising network, however, is the same one capable of recording other information such as the web browser used, the IP address, the operating system, the screen size, the time zone and other info which are called "fingerprints".
Later, when you visit a site with ads from the same network as the site visited in an incognito mode, the browser's fingerprint is recognized (albeit with varying degrees of precision) and the ads are again based on what you were looking at. before, even if it was in Incognito mode.
Even using different web browsers does not change the fact of being followed by advertising.
When accessing the same online account on more than one browser or devices, the account provider associates the different fingerprints with the account and the personalized advertisements can continue to follow us from one browser / device to another.
If you use different devices, computers or smartphones to access the various accounts, for example from one Facebook and the other only the Google account, but they connect to the same wifi networks and visit the same sites, these devices are associated and recognized as the same person.
This may suggest that there is a risk that members of the same family may see the same announcements, and indeed it is so.
If you have never actually visited a particular site, but other people have done so, you may see contextualized ads for that site because our profile is similar to other people.
If you then share an IP address with people who have visited a certain site that we have never seen, then if, as normal, everyone at home accesses the internet from the same router, then it is possible that personalized ads are displayed from that site.
It is even true that if we are in a place where there are people who keep the location active and one of them sees a certain site, it is possible to be included in a group which will be shown the same advertisements.
As far as the use of smartphones is concerned, even there it is followed in all respects.
There are app location services, such as Facebook and Google Maps, which follow our movements and perfectly know what we are going to look for.
There are normal apps, which do not have cookies, but use a unique device ID number and pass it on to the creator of the application.
If you open one app and then another, they may appear on this personalized ads from the previous app.
The device ID is associated with the various app accounts and advertising becomes targeted towards the ID.
Ads based on your apps will also appear when you use the same accounts on your computer.
On Apple, Android and Windows devices it is possible to disable or reset the device ID, this will not prevent ads from being displayed, but will greatly reduce the amount of personalization.
Voice assistants also store requests and then display personalized advertising on the sites visited.
A bad thing to note is that in some cases the voice assistant can activate itself, without being called back (because its voice recognition system can make mistakes in unpredictable ways).
After reading all of this, you may also have some fear of turning on your computer, even if personalized ads are not really a problem in the end.
You can certainly limit the personalization of the ads, for example by denying it to Google and Facebook, often deleting cookies and deactivating or resetting the advertising ID of the phone.
We have seen in another article how to block personalized advertising from Amazon, Google, Facebook and other sites and also how to prevent Facebook from following us and knowing what sites we are looking at, even using a browser extension.
Unfortunately, it is not possible to control all the monitoring, Facebook and Google can collect data about us even if we do not use their own account, but it can also become very limiting to give up certain services that, undoubtedly, work too well (Like Google Maps).
The invasive tracking and the collection of data in secret has pushed the European Union to implement the GDPR law and to oblige websites and online services to give warnings on the use of cookies and personalized advertising.
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