Cookies – according to the European commission.
A cookie is a small piece of data that a website asks your browser to store on your computer or mobile device. The cookie allows the website to “remember” your actions or preferences over time.
Most browsers support cookies, but users can set their browsers to decline them and can delete them whenever they like. However, it might make your uses of several websites slower.
More to find at the website of the EU Commission Internet Handbook.
Picture by Pezibear @Pixabay