When it comes to blockchains like Gather, which are essentially distributed databases, the network's nodes must agree on the current state of the network. Consensus procedures are used to obtain this agreement.
We use the term "consensus" to refer to a universal agreement. Consider a group of people who are going to see a movie. A consensus is reached when there is no dispute on a given film choice. In the most extreme instances, the group will break up.
In the case of blockchain, the process is codified, and obtaining consensus means that at least 51% of the network's nodes agree on the network's next global state.
Consensus mechanisms (also known as consensus protocols or consensus algorithms) enable distributed systems (computer networks) to collaborate while remaining secure.