Synchronous - Having a constant time interval between successive bits, characters or events. Synchronous transmission uses no redundant information to identify the beginning and end of characters, and is faster and more efficient than asynchronous transmission, which uses start and stop bits. The timing is achieved by transmitting sync characters prior to data; usually synchronization can be achieved in two-or three-character times.
This term is commonly used in software engineering, programming, scripting, application design, testing, and development lifecycle work.