You can own only a portion of a bitcoin. It is divisible like the dollar. However unlike the dollar, it holds value.

$100 of BTC from 2020 is now worth $2000.

$100 of USD from 2020 is now worth $80.

"Dishonest scales are an abomination to the Lord, but a just weight is His delight." - Proverbs 11:1

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