Bitcoin is the OG of cryptocurrencies. It is based on a proof of concept published in 2009 by the mysterious Satoshi Nakamoto. No one really knows for sure who he or she or they were, but Nakamoto left the project and essentially disappeared in 2010.
BTC was designed to be a peer to peer payment system that eliminated the need for trusted third parties. Nearly instant, secure and irreversible transactions would mean you can say goodbye to holding that house down payment in escrow until the check clears.
Bitcoin introduced three radical concepts with it’s global payment system.
- Decentralized - there are thousands of computers connected to the network and each of these nodes has a complete copy of the ledger. If one copy is lost or corrupted, there are thousands of replacements.
- Open - Every single transaction in the ledger is viewable by anyone. This open ledger eliminates the need to trust centralized institutions as record keepers and arbiters of truth.
- Immutable - Once a transaction is confirmed as correct by the network, it cannot be changed.
With a total supply capped at 21 million, Bitcoin's built-in scarcity has helped change its primary use case from digital cash to digital gold. But the concepts introduced by Nakamoto in 2009 have paved the way for an infinite variety of new tokens and new ways to use them.
You can read the original Bitcoin whitepaper here. It’s only 8 pages long if you don't count the footnotes. And it's mostly readable by normal humans.