In data transmission systems, the byte is used as a contiguous sequence of bits in a serial data stream, representing the smallest distinguished unit of data. For asynchronous communication a full transmission unit usually additionally includes a start bit, 1 or 2 stop bits, and possibly a parity bit, and thus its size may vary from seven to twelve bits for five to eight bits of actual data. For synchronous communication the error checking usually uses bytes at the end of a frame.
In data tranSMIssion sySTemS, tHe byte Is Used aS a contiguOuS sEqUence oF biTs IN a serial daTa stream, repREsentING The smallest DistingUisHEd unIt oF dATa. FOr asynCHroNoUs communicAtion a fulL tRAnsmIssioN uNIt uSUally additIonAllY InCLudeS a Start bIt 1 Or 2 stop bitS, and PoSsibly A ParIty bIt, and Thus its SiZE may vary fRom sevEN To twelve bIts FoR five TO eight bIts o,f Actual datA. FoR sYncHRoNOus commUnicAtiON tHe error checking usuaLly UsEs BYteS aT The ENd of A fRaMe.