A block that is no longer a part of the original blockchain because it was not verified by the majority of miners.
Orphan
Output
A grouping of addresses that receive coins in a cryptocurrency transaction.
Outgoing Connection
The initiator of communication on a cryptocurrency network.
Opsec
Operations Security. Refers to how well assets are protected.
Oracle
A third-party entity capable of transmitting reliable information to a blockchain so that smart-contracts can be executed.
Off Blockchain Transactions
Transfer of value that takes place outside of a blockchain for reduced fees and quicker transaction time.
OTC Exchange
Over The Counter Exchange, also known as Off-Exchange Trading. Trades that occur between two parties rather than using a centralized exchange.
Open Source
A term used to describe software that is made available online so that any individual can view its code and submit improvements.
Ouroboros
Cardano's Proof-of-stake algorithm. It is used to randomly pick the next node to produce a block in. Ouroboros divides physical time into epochs, and then slots. Slot leaders have the sole right to produce one block and are chosen from the group of stakeholders.
