What is a cid number?

A CID (Caller Identification) number is a unique identification number assigned to a caller by telecommunications companies. It is used to identify the caller when making phone calls and is transmitted along with the phone call. CID numbers are usually displayed on the recipient's phone before they answer the call, allowing them to decide whether to answer or not based on the displayed number.

CID numbers can be blocked or spoofed by callers looking to hide their true identity, which can be a nuisance for recipients. It is important to be cautious when receiving calls from unknown numbers and to avoid giving out personal information to unfamiliar callers.