Typically this is indicated with a band of black or red electrical tape but other colors may be used wrapped around the wires insulation. The black hot wire from the feeder cable is connected to the common terminal on the first switch.
Electrical Basics Wiring A Basic Single Pole Light Switch
Which wire is switched black or white. Under those conditions a black wire should be always hot and always on. The white wire is the neutral and all other colors are hot. They may use other colors for switch wiring such as yellow or tan. Orange wires frequently are used to interlink smoke detectors. When a white wire is augmented with a red or black color marking this often indicates that it is being used as a hot wire rather than a neutral wire. Black is hot white is neutral but it always pays to test.
How to wire a switch with white black and ground wires. The ground wire goes to the green screw. In north america the rule is that in single phase household wiring normal outlets black is live and white is neutral. The power source or feeder wire is a 2 wire cable with a ground meaning it has one black hot wire one white neutral wire and a bare copper ground wire. But in a passage set switch you might see red or white being used for a potentially live wire or the installer might just have made a mistake. Electricians often use black red or blue wires to deliver electricity to a circuit from the main panel.
The hot wire in a 120 volt residential ac circuit usually is coated with black insulation while the return or neutral wire is white. Neutral wires do not connect to switches. The white wire goes to the white metal screws on an electrical outlet. When you connect an outlet or light switch the black wire goes to the brass screws. Typically the circuit would be wired like this b black w white at light switch. In a 110 volt setup an additional wire usually red or blue normally indicates a hot wire controlled by a light switch.