Hi there
What's the most simple way to describe what bitcoin is for people?
Will be cool to read in the comments some new creative ways to do that!

I think it is difficult for an average 7 years old people to understand the bitcoin at its simpliest explanation because at that age children aren't fully capable of absorbing data and information such thing however, if you are to explain what bitcoin is then it should be explain that bitcoin is a currency that can only be use via intenet to have transactions.