Transaction
/trænˈzækʃən/
noun — "atomic unit of work in computing."
Transaction is a sequence of operations performed as a single, indivisible unit in computing or database systems. A transaction either completes entirely or has no effect at all, ensuring system consistency. It encapsulates multiple read, write, or update actions that must succeed together, maintaining data integrity even under concurrent access or system failures.
Durability
/dʊˈrəbɪlɪti/
noun — "changes survive failures permanently."
Durability is a property of transactions in computing and database systems that guarantees once a transaction has been committed, its effects are permanent, even in the event of system crashes, power failures, or hardware malfunctions. This ensures that committed data is never lost and can be reliably recovered, maintaining the integrity of the system over time.
Isolation
/ˌaɪ.səˈleɪ.ʃən/
noun — "operations shielded from external interference."
Isolation is a property of transactions in computing and database systems that ensures concurrent transactions execute independently without undesired interaction. Each transaction appears to operate in isolation from others, preventing phenomena such as dirty reads, non-repeatable reads, and phantom reads. This property preserves data consistency and integrity in multi-user or multi-process environments.
Atomicity
/əˈtɑː.mɪ.sɪ.ti/
noun — "all-or-nothing execution in operations."
Atomicity is a property of operations in computing and database systems that ensures a sequence of actions within a transaction are treated as a single, indivisible unit. Either all actions in the transaction complete successfully, or none are applied, leaving the system in a consistent state. Atomicity prevents partial updates that could lead to data corruption, inconsistencies, or unpredictable behavior.
ACID
/ˈeɪ-sɪd/
n. “Guaranteeing your data behaves — no surprises allowed.”
ACID is an acronym describing the foundational properties of reliable database transactions: Atomicity, Consistency, Isolation, and Durability. These principles ensure that when data is read, written, or updated, it behaves predictably — even under crashes, concurrent access, or network issues.