Initially, direct current was used for power transmission. It was only in the 1950s that people realized the merits of alternating current over the other.
Although the two are used today, alternating current is more accepted worldwide. It is used for bigger appliances as well as in houses. Let us see why.
One of the main reasons for having AC for domestic purposes is that it causes very low wastage of power. It is seen that even at high voltages above 110 KV, less energy is lost in transmission. Yet another peculiarity of AC electricity is that voltage can easily be changed from high voltage to low and vice versa. This in turn makes it suitable for long distance transmission, unlike DC.
Alternating current is also known to be capable of powering electric motors. Thus, it is useful for high-end appliances like refrigerators, televisions, computers etc.
In terms of safety too, AC is preferred to DC power.
It is for these reasons that most countries in the world favour AC than DC power.