Aka. Single operation, single object, and real-time order. It provides a real-time guarantee on the behavior of a set of single operations on a single object(e.g. distributed register). In plain English, under linearizability, writes should appear to be instantaneous. Imprecisely, once a write completes, all later reads (where “later” is defined by wall-clock start time) should return the value of that write or the value of a later write. Once a read returns a particular value, all later reads should return that value or the value of a later write.