What is Bitcoin, as if you were to explain it to a child?

What is Bitcoin, as if you were to explain it to a child?

To a child knows what is money, it'll be easy to understand for him.

• It is kind of currency or money not physical but digital which flows through the internet.
• It is decentralized which means there is not only one body which controls the money. No middle man like bank to exchange the currency.
• It is created by a process called mining in which a solution of a mathematical problem is to be find while performing a transaction.
• Anyone in the world can join to find out the solution and if one gets the solution then gets rewarded with brand new bitcoins like money.
• You can see anybody's transaction in the world.