In the previous post about cookies, we discussed what browser cookies are and where we can find them. Let's break things down further because there are different types of cookies out there.
Cookies characterized by a direct relationship between the browser and the server of the website the user visits are called “first-party cookies”. They are often used to improve the experience of the website for the user (e.g. remembering language settings, previously entered login details, items in a shopping cart, etc.).
In addition to “first-party cookies”, there are “third-party cookies”. These cookies are set by third parties such as marketing vendors. One example would be cookies set by Facebook Ads with the help of another piece of code added to a website called a "pixel". In this setup, user behavior data on a website can be collected and shared directly with the servers of a marketing vendor. Such data can then be leveraged to determine how ads would be shown when the user visits other websites within the ad vendor’s network.
How Cookies Affect You
First-party cookies are generally associated with ensuring a good user experience on a website without sharing data with any other parties.
Third-party cookies, however, are associated with sharing data with ad vendors and other parties existing beyond the scope of the website being visited. Privacy-oriented technologies and legislation, therefore, tend to be directed particularly at third-party cookies.
If a user accepts third-party cookies, the user may become the target of specific marketing campaigns. If a user blocks or does not accept cookies, the marketing vendor will not be able to receive data from the user’s browser, making it harder to optimize advertising campaigns targeted to the user.