ACID rule of thumb for transactions

A transaction must be:

1. Atomic - It is one unit of work and does not dependent on previous and following transactions.
2. Consistent - Data is either committed or roll back, no ?in-between? case where something has been updated and something hasn't.
3. Isolated - no transaction sees the intermediate results of the current transaction).
4. Durable - the values persist if the data had been committed even if the system crashes right after.