The standard connector for thin ethernet. A device for separating network traffic. Explained in the class. Older and newer standards for twisted pair copper cables. Thick and Thin ethernet are both coaxial cables, as is Cable TV cable.
Half duplex can only transmit or receive.
Each device at each end of the connection has to have the same duplex setting or the connection will fail. In theory a 100Mbit full duplex connection becomes 200Mbit, but rarely will both directions be operating at full speed. Cable, generally in pairs, which allows laser light to be used as a transmission medium for data or other signals. Somewhat more fragile than copper. Allows much greater distances than copper cables.