 The rapid update of modems led to a similar rapid increase in BBS use, which was helped by the fact that BBSs could control the modem simply by sending strings, rather than talking to a device driver that was different for every direct-connect modem.The 300 bit/s modems used audio frequency-shift keying to send data.In this system, the stream of 1s and 0s in computer data is translated into sounds which can be easily sent on the phone lines.