A bowl of delicious looking cookies on a brown table

We are all bombarded by website cookie agreement ‘offers’ on literally every website we visit. These agreement pop-ups are often unfriendly and downright annoying. Yet, why do internet websites go to such lengths? Sure, we’ve heard that website cookies track data. We might have even heard that this data is used to sell ‘products’ to us. But what exactly goes on under the hood here? Just how much of a necessity is there for these cookies? And just how much of a threat is this cookie-monster to us and our privacy? Bad jokes aside, this article tries to describe the 5 most important uses for tracking cookies in modern browsers and apps.

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Remembering your login data

The most common use for cookies is to help you log in to websites. For example, when you log in to your Gmail or Facebook, you are often sent a cookie. This cookie is then stored on your computer. As a result, when you visit other websites that use the same login method, it will automatically send the stored cookie along with all of your details. This saves you from having to type in your information every time you visit a site that uses the same login method.

This is done so that users don’t have to remember an infinite number of usernames and passwords. This makes it much easier to quickly log into popular sites without having to remember all of your different usernames and passwords – especially for sites that require multiple logins.

On the other hand, one can easily see the security concerns here. It is the user’s responsibility to ensure security of the cookie information on the local hard drive. If this information were to be stolen, the user’s online accounts are all but safe. There are multi-factor logins that protect users these days, but still, the security concern about the local cookie storage remains.

Helping apps run smoothly

Cookies can also help applications run more smoothly by tracking how users interact with the app / website and improving the user experience each time they return. For example, if the website / app notices the bouncing back and forth between two pages on an app, the website / app is likely to send a cookie to the user’s computer. This way, next time the user visits, they won’t have to bounce back and forth – instead, it will automatically take them straight there. Cookies like this are key in making common apps work efficiently and therefore provide a better user experience.

Letting you watch videos & online TV

Cookies also play a vital role in letting you watch TV and videos online – such as YouTube or Netflix. When watching these types of videos or TV shows, cookies usually collect information about what content is being watched and when – helping video providers build up their database of information about what you want to watch and when we you to watch it. Eventually this data will be used for targeted advertising (more on that in the next point).

This category of cookies has both pros and cons. Apps like Spotify use this to improve your music discovery experience, whereas video / audio service providers also use this data to keep you engaged with their service, and not get away so easily. This creates a drug-like effect. As they say, “Pick your pill…”

Giving you personalized content / suggestions / ads based on your browsing history

One of the main ways cookies are often used is through targeted advertisements. This is done by keeping track of what content people see online and what they click on, which helps advertisers create a more personalized experience for users by showing them more relevant ads based on their interests and browsing history. For example, if a person searches for “flowers” online one day, they might get ads about flower shops or flower arrangements popping up over the next few days while browsing other websites – even though they don’t remember ever clicking on them. This is a very common way that cookies are used, but it’s also one of the most controversial ways they are used.

Furthermore, many users these days have a spooky hunch that their phones are ‘eavesdropping’ on them. Someone might have had a conversation about baby elephant toys with their friend, only to find ‘baby elephant toy advertisements’ on their social media feed a day later. In cases like these, it is unlikely that the phone is ‘listening in’ on its user’s conversations. What’s going on here is usually a clever combination of location-tracking (or proximity tracking) and cookie-data based targeted advertising. For instance, it is more likely that the friend actually searched the term ‘baby elephant toy’, and location-tracking indicated that these two people were in close vicinity before this search occurred. Hence, the advertising algorithm decided to flash advertisements related to this key phrase on both their feeds. It’s more complicated than that, but you get the gist. One can deduce a whole lot of human behavioural patterns from combinations of such data sources; the microphone or the camera would hardly be needed. I don’t know whether to laugh or cry about that though.

Helping you share content on social media

Finally, cookies can help with sharing content on social media. For example, if you’re browsing news articles and find one that you want to share with your friends, you might get a cookie alert asking if you’d like to share this article on your Facebook or Twitter account. This is done so that when people visit your Facebook or Twitter page, they can see what you’ve recently been reading online – even if they haven’t visited the website themselves!

Here, the internet service providers use one of the oldest tricks in the book – your social needs. If you find something interesting, your social-needs drive you to share it. In the same way, you are likely to consider stuff that your friends find interesting. In theory, this should lead to a well-functioning society. But when systems are optimized for exploiting human social-needs, the tail starts wagging the dog, and things ‘could’ go south over time. Time will tell.

On that rather not so bright note, I hope you found this article interesting and useful. If you’d like to get notified when interesting content gets published here, consider subscribing. If you want to get into the nitty-gritty technical background about cookies, check this page out.

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