Answer:
An IP Address
Explanation:
Every computer or networking device has its own IP address. It is a series of numbers that will uniquely identify a particular computer on the internet. Since the computer connects to the internet via a router (provided by the Internet Service Provider), it is the router's IP address (or simply the network address) that is shared on the internet. So, the IP address is not exactly a reliable way of linking you to what you do on a computer.
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