2.7 ECDSA & Schnorr: Two Flavours of Signatures

Bitcoin originally used a signature style called ECDSA. Think of it as a perfectly serviceable signature pen — it works, it's secure, but every signer has to sign their name separately on the page.

In 2021, an upgrade called Taproot added a new style called Schnorr. Schnorr signatures have a special property: if multiple people need to sign, they can blend their signatures into a single combined signature that looks exactly like one person signing.

Why does that matter? Two big reasons:

Privacy: A group account requiring, say, 3 of 5 signers looks identical on the blockchain to a single person sending coins. Outsiders can't tell which one it is.

Lower fees: One combined signature takes less space than several individual ones, so transactions are cheaper.

Most modern wallets are gradually moving to Schnorr-based Taproot addresses (they start with 'bc1p').