# Electronic – negative current

amperagebasiccurrent-sensingelectricity

I understand that voltage is relative to ground, so that can be negative.
However, I'm currently looking at current-sensors (ACS712 current sensor) and in the performance characteristics table, it specifies the Optimized Accuracy Range.
In the case of this sensor, it's being specified in Amps, ranging from -5 A to +5 A

I can't find anything explaining how you could have a negative amperage. As far as I know, electric current is the rate of flow of electric charge within a (part of a) circuit.

How could the flow of charge sensed by the sensor be negative?