DIKU is an acronym used in digital communication to express confusion or disbelief when someone contacts you and you don't recognize their name or number. It is often used in situations where someone is trying to start a conversation with someone they don't know or remember.
DIKU is not a widely recognized or frequently used acronym in digital communication. It is more commonly used in specific situations where people want to express confusion or disbelief when contacted by someone they don't recognize.