Visit this website (or copy and paste https://www.deviceinfo.me) and it will show you a long list of all the identifiers that every website you visit can find out about you, your location, your device etc… All these different data points then used to create a “fingerprint” of your web browser, allowing the rest of your web activity on that same browser/device to be trackable.

NB: You can visit this website from any of your devices (mobile or desktop/laptop).