Archer missile
From Halopedia, the Halo wiki
Archer missiles are fired from UNSC capital ships. They can fire at very high rates and are armed with varying payload yields. They are found on almost all ships and the round shape of the Archer missile pod is very distinct. They have tracking systems, which are very effective to coordinate attacks with MAC rounds. They are very inaffective against single ships, which is why most capital ships are armed with varying sizes of roterary cannons.
Unfortunately, Covenant point defense technology can eliminate up to half of the missiles before they reach a target. There are only two known instances in which the Covenant disabled Archer missiles: the first occurred during the Battle of Sigma Octanus, when a Covenant spy ship that was orbiting Sigma Octanus eliminated the Archer Missiles so Captain Jacob Keyes rammed the spy ship; and the second occurred during the Battle of Onyx, when the UNSC fired their first salvo and the Covenant used pinpoint lasers to disable them. Even those missiles that do manage to impact the shields or hull of a Covenant ship generally fail to do any significant damage. It takes many hundreds of missiles, and usually an existing hull breach created by a MAC round to make these missiles truly effective.
Vessels such as the frigate UNSC Commonwealth employ racks of 180 Archer missiles, while the destroyer UNSC Iroquois and the cruiser UNSC Pillar of Autumn use oversized Archer missile pods which can launch up to a thousand missiles.
