Human wave attack, also known as human sea attack, is an offensive infantry tactic, in which an attacker conducts an unprotected frontal assault with densely concentrated infantry formations against the enemy line, intended to overrun the defenders by engaging in melee combat.
According to U.S. Army analyst Edward C. O'Dowd, the technical definition of a human wave attack tactic is a frontal assault by densely concentrated infantry formations against an enemy line, without any attempts to shield or to mask the attacker's movement. The goal of a human wave attack is to maneuver as many men as possible into close range, hoping that the shock from a large mass of attackers engaged in melee combat would force the enemy to disintegrate or fall back.
The human wave attack's reliance on melee combat usually makes the organization and the training of the attacking force irrelevant, but it requires either great physical courage, coercion, or esprit de corps for the attackers to advance into enemy fire. However, when matched against modern weaponry such as automatic firearms, artillery and aircraft, a human wave attack is an extremely dangerous and costly tactic in the face of devastating firepower. Thus, for the human wave attack to succeed on the modern battlefield, it is imperative for the attackers to charge into the enemy line in the shortest time and in the greatest numbers possible, so that a sufficient mass can be preserved when the attackers reach melee range.
However, this solution usually means that the attackers must sacrifice concealment and cover for numbers and speed. Because of this trade-off, human wave attacks are normally used by an attacker with a lack of tactical training, or one who lacks firepower and the ability to maneuver, but whose main advantage is motivating and controlling their men.