How does alternating current differ from direct current?

Hint : A unidirectional flow of current with no change in magnitude and polarity is known as direct current. Whereas, an alternating current or voltage is one, which changes its magnitude and direction at a regular interval of time. So, they are totally different from each other.

Complete step-by-step solution:
Difference between alternating current and direct current are –
The alternating current changes its direction while flowing, but direct current remains constant during the flow.
The alternating current has a frequency indicating how many times the direction of the current has changed, whereas, because of not changing the direction of the flow, direct current has zero frequency.
Alternating current has power factor from $0$ to $1$ , but direct current is always constant (zero).
Alternator generates AC current, while DC current is generated by photovoltaic cell, generator, and battery.
The load on alternating current can be capacitive, inductive, or resistive; but the DC load is resistive always.
AC current can be a sinusoidal wave, square wave, or triangular wave, whereas, in DC current graph, there is a straight line which shows the magnitude and direction are constant.
Rectifier is the device which converts alternating current to DC, and DC can be converted to AC using an inverter.
Alternating current is widely used in industrial and consumer electronics such as AC, freezer, coolers, laundry, lamps, fans, while DC is used in electronic equipment and appliances, such as watch, laptop, cell phone, Sensor.
AC can be transmitted over long distances with some attenuation while DC can be transmitted very far with very low attenuation using HVDC.

Note:
While getting an electric shock, it is more difficult to pull the hand back in case of DC as it flows continuously, but AC current goes to zero. In contrast, muscle contraction is continuous for electric shock with DC current, whereas for AC current, a person undergoes a series of muscle contraction, causing severe damage. So, we cannot say properly which current is more dangerous.