“Bitcoin has no physical form. It doesn’t exist in any way. It is entirely intangible. It cannot be touched. It is simply a digital form of money. But it is a digital form of money that is entirely different from everything we’ve seen before. What it does that is different is that it is not a form of money that is recorded in the database or records of a company. Is it not a digital form of money that represents a debt owed to a central bank or government. It is not a digital form of money that has been issued by a sovereign, a central bank, a nation, a king. It is a form of digital money that has been issued by complex and energy-intensive computation; on the internet; is recorded on every computer that participates in the Bitcoin network; is validated independently by every computer that participates in the Bitcoin network; cannot be forged; cannot be counterfitted; cannot be seized or frozen; can be transmitted anywhere in the world as information; can be verified independently by anyone who receives it; and is not controlled by anyone.”
-Andreas Antonopolous, in the YouTube video ‘Bitcoin for Beginners: Bitcoin Explained in Simple Terms’, in 2017.
(read about Andreas Antonopolous on Wikipedia)