Edit / A property of a unit of work (a transaction) such that the operations of the unit of work are either all performed, or none of them are performed. For example, if entering a credit card sale is composed of three distinct steps (swipe, key in PIN, accept ammount) then the transaction should be atomic. That way, if the swipe machine shuts off after the first step is complete, the transaction will not be performed at all. Thus, there will be no partially completed transaction to deal with.

the transaction must occur completely or not at all.

Property of a transaction in which it will either complete as a whole unit of work or be rolled back.

Procedural processing that maintains a single processing thread, without any wait states. See also single-threaded processing.

Atomicity is a type of serialization that refers to the indivisibility of a small number of actions, such as those occurring during the execution of a single instruction or a small number of instructions.

Degree of atomic attraction; equivalence; valence; also (a later use) the number of atoms in an elementary molecule. See Valence.

(n.) The condition of an operation that is never interrupted or left in an incomplete state under any circumstances.

Changes made to protected resources within the same unit of work are atomic; either all happened or none happened.