NAND Gate:

A Logic NAND Gate is a series combination of a digital logic AND gate and a NOT gate.

A NAND (Not - AND) gate has an output that is normally at logic level "1" and will only go "LOW" to logic level "0" if ALL its inputs are at logic level "1". Because it is one of the most common types of logic gates, the NAND logic gate is sometimes referred to as a "general purpose" gate.

---