Bitcoin Terms Beginning with O

Off-chain is a term used to describe any data that is not registered on the Bitcoin blockchain. Bitcoin transactions on other layers, including the Lightning Network, are off-chain transactions. Off-chain transactions are usually quicker and cheaper than on-chain transactions.

The Office of Foreign Assets Control (OFAC) is a department of the Treasury responsible for enforcing economic trade sanctions and embargoes.

On-chain is a term used to describe any data that is registered on the Bitcoin blockchain. On-chain data is almost exclusively comprised of Bitcoin transactions.

An operation code, or opcode, is a basic command of some computer languages. Bitcoin’s scripting language, called Script, has its own set of opcodes.

Open-source describes a project whose source code is publicly available and licensed such that individuals can use and alter the source code freely.

Operating Expenditure is the recurring amount of money a business spends to continue conduct standard business. Operating expenditure is equivalent to the variable cost of production.

An options contract gives the buyer the option to execute a predetermined trade at some point in the future. If the trade is favorable they will execute it, making a profit.

The Oracle Problem describes the as of yet unsolved problem of integrating external data, such as the score of a sports game, into a smart contract on the blockchain in a trustless manner.

An order book is the list of all the pending orders for a particular asset. Order books help traders understand market activity.

Order execution is the manual or electronic process of accepting and completing a buy or sell order in the market on behalf of a client. Order execution best practices are regulated by the SEC and the security concerns or needs of individual exchanges.

An orphan block is a valid block that was excluded from the blockchain because another block was mined at the same height and was part of the longer chain.

An OTC Desk is a business dedicated to the trading of certain assets. OTC Desks are commonly used by traders looking to execute large orders.