Both first- and third-party cookies are data about users visiting a given website. There is, however, a fundamental difference between them. First-party cookies are created by the host's domain, i.e. the one currently visited by the user. Third-party cookies are created by domains other than the one that the user is visiting at the time and are mainly used to track user behaviour and advertising purposes.
Let us explain it on the example of social media buttons "Like" and "Share", which we all like to click on. Social media that allows users to log in, share and like content on third-party sites places cookies on their device. This means that even if you are not logged in (e.g. on a social networking site), these files still track your activity, and when you return to them, they are able to show you content that you are interested in.
Why is it worth replacing them with first-party cookies? Firstly, because they will be blocked. Secondly, because they are perceived as more friendly. Thirdly, because they will not interfere with the functioning of tools for personalising and optimising the purchasing process in your online shop.
Still hesitating? Do not expose your business to losses and learn how to quickly and easily implement first-party cookies in your shop. It's all written in the article titled First-party cookie implementation instructions.