Synchronous is defined as existing, occurring or arising at precisely the same point in time, and asynchronous means the exact opposite. These two terms are frequently utilized in computing and networking.
Synchronous and asynchronous are applicable to communication. For example, synchronous communication occurs in real time, such as when two people are having a conversation. Asynchronous communication does not necessarily occur in real time. For example, asynchronous communication occurs when a transmitter sends an email to a receiver. The receiver reads the email at a point in time that is not exactly contemporaneous with the sending or transmission, rendering it asynchronous.
The terms synchronous and asynchronous are commonly utilized in the realm of digital communication. In this context, synchronous applies to a common timing signal that is specifically established to determine when individual bits of data are transmitted. A synchronous transmission allows for data transfer at a particularly high rate of speed.
Conversely, in the context of digital communication, asynchronous means that there is no timing requirement in place associated with data transmission. Because of this structure, each individual bit of data is individually signaled via the transmitting agent or device. An asynchronous method does not operate at the same speed as a synchronous transmission.