Bitcoin Terms Beginning with U

The U.S. Treasury is an executive agency that manages the money supply for the federal government, collects tax revenues, and borrows funds to fuel government spending.

The Uniform Commercial Code (UCC) is a set of laws that regulate the sale of commercial goods and investment products. The U.C.C. is not federal law; it is a collection of statutes that each state adapts for implementation in their jurisdiction.

A unit of account is a function of money. A standardized unit of account allows investors to measure performance and economists to measure profit, cost, and prices.

A Unix timestamp is the number of seconds since January 1, 1970 UTC. Timestamps are used in blocks to ensure that blocks accumulate in a chronological order.

A UTXO is a discrete piece of bitcoin. Bitcoin does not use accounts and balances. Instead, individual pieces of bitcoin are owned by individuals, analogous to physical coins or cash.

In bitcoin mining, uptime is a measure of how often a machine has been producing hashes over the total amount of time it could have been producing hashes.

A User-Activated Soft Fork is an update or change to the Bitcoin network’s protocol initiated by users (nodes), who integrate new code into their Bitcoin nodes.

Universal Time Coordinated (UTC) is a specific timezone and is used as a standard for international timekeeping. UTC used to be known as Greenwich Mean Time or GMT.

Utreexo is a proposed light client scheme which would consolidate the UTXO set into a Merkle Tree, allowing users to maintain only the UTXO set and very little other data.

The UTXO set is the comprehensive set of all UTXOs existing at a given point in time. The sum of all UTXOs will yield the precise current supply of Bitcoin.