If you are going to teach it with the child who is 7 year old, you are going to use the word that can easily understand or comprehend them, but it really depends on the child if the child is not interested they will not easily understand it coz we all know that age is not the age that a child will give time to understand it. There is a child who are very curious but only few.
Well, Bitcoin is a currency, unlike the normal fiat, it is not tangible, that is why it is called digital currency. It was brought by a technology called blockchain, which is decentralized. Bitcoin is an optional tool for exchange of value and services, so it can be a subject for investment that can give you a promising decent return, because of its volatility. The coverage right now is still on its growing stage, but gaining popularity so quickly.