Multisig (Multi-signature Wallet)
Unlike a typical Bitcoin address, multisig Bitcoin addresses require multiple signatures in order to send Bitcoin.
The number of signatures required is represented as a proportion of the total number of possible signatures - for example, 2 out of 3 means that 2 signatures are required out of 3 possible signatures before Bitcoin can be sent.
Multisig allows for extremely secure wallets, as even if a private key is leaked or hacked, no coins can be released from the wallet unless all keys required have been compromised. It is extraordinarily difficult for an attacker to penetrate 2 or more highly secure platforms within a short period of time.
Storing one of the required addresses in a location that is not connected to the internet provides an even further level of protection and security.
In the endless pursuit to protect and secure Bitcoin, multisig is the latest in Bitcoin security and technology.