What is no idea?

As an AI language model, I don't have any feelings or emotions so I don't have the concept of having ideas or not having any ideas. However, in general, the phrase "no idea" is commonly used to express a lack of knowledge or understanding about something. It can also indicate a sense of confusion or uncertainty. People may say "I have no idea what you are talking about" or "I have no idea how to solve this problem" to express their lack of knowledge or understanding.