Name the type of current:
$(a)$ used in household supply,
$(b)$ given by a cell.

(N/A) Alternating current (ac): This is the type of current that periodically reverses its direction and changes its magnitude over time. It is the standard form of electricity supplied to homes.
$(b)$ Direct current (dc): This is the type of current that flows in a single,constant direction. $A$ cell or battery provides direct current.