Serial transmission
Sequential data transfer, one bit at a time, using only one electrical circuit.
Synchronous transmission
Data transmission during which both communicating devices are synchronized by a common clock. Using this mode eliminates the need to systematically add a stop bit and a start bit to each transmitted character.
Terminal mode
Required simulation mode for computers to transmit data. In terminal mode, the computer acts as though it were a dumb terminal rather than a data processing unit. Keystrokes go directly to the modem whether they are modem commands or data to be transmitted via the telephone lines. Received data are displayed directly on the screen.
Terminal
A unit whose keyboard and screen are used to send and receive data via a communications link. A terminal differs from a micro- computer in that it has very little or no internal processing capabilities.
Transmission rate
Number of bits transmitted per second (bit/s). Communications channels using modems on telephone lines are set to binary rates, generally 2400, 9600, 14400 or 28800.
Xmodem
The first of a family of error correction software protocols used to transfer files between modems. These protocols are in the public domain and are available on many servers. Ymodem and Zmodem are later protocols.
66 Sportster Winmodem 33600 & x2/56K - User's manual