5V

5 Volts, the supply voltage for many electronic circuits. When digital electronic circuits signal a logical true - or "on" value, it is by connecting an output to 5V.

In many devices, the 5V connection and other connections (digital inputs and outputs) will connect directly to some electronics that must have values between 0V and 5V and no more. If you put a higher voltage on these connections, you will almost certainly damage the device.