The term "multisig" stands for "multi-signature" and it's used to describe accounts associated with more than one private key. The account is created with a list of owners and a policy `m-out-of-n` when transactions are approved by at least m owners, they can be executed.
In blockchain each transaction involves the usage of public-key signature; each blockchain participant owns a private/public key pair. The participants use the private keys to sign a transaction and all other participants can verify that signature using the signer's public key.
With a multisig account, each transaction requires the signature of many accounts before being executed. One participant (who is among the multisig account owners) can start the transaction, but only when the other owners approve that transaction, it will be executed.
The multisig account eliminates the single point of failure in case of attacks and it allows the implementation of a variety of use cases where one or many parties are involved. Here below some examples.
The RIF Multisig offers all of the features of Gnosis Safe + additional SDK methods, bringing the multisig solution to RSK and the Bitcoin ecosystem in a seamless way for the first time. It also helps to bring the DeFi for Bitcoin experience in line with Ethereum on security and UX. Developers can integrate the open source solution with support from the RSK Apps & Services team.