Homing Anti-Radiator Missile (HARM)

The Homing Anti-Radiator Missile (HARM) is a specialized missile used in ship-to-ship warfare. Unlike other missiles that are designed to blast apart armored ship hulls, the HARM is designed to strike at a ship's glass jaw: the heat radiators. Without these fragile arrays, a starship is unable to dissipate waste heat and will cook its crew alive unless it can cycle down its fusion reactor in time. The HARM uses IR sensors to identify a ship's radiators and flies towards them.
When the HARM is close enough to the target, it unleashes a barrage of fragments toward the ship, shredding radiators which are usually made of thin hyper-conductive alloys. These fragments are rarely large enough or fast enough to penetrate armored ship hulls, but they are incredibly effective at the task of destroying radiators. As a secondary effect, the hail of fragments can damage more sensitive communication and sensor systems, and pose a threat to any personnel conducting EVA in the vicinity. Civilian ships without substantial hull plating are also at risk of catastrophic hull breaches.
While the fragments from a HARM detonation are slow compared to point defense cannons or rail guns, the lack of friction means they do not lose speed for quite some distance. Any fragments that miss their target pose a hazard to the radiators and sensitive equipment of any ship in the vicinity. For this reason, HARM missiles are directional, firing their fragments in a roughly conical spray to reduce the risk of colateral damage to friendly or neutral ships.
Since HARM missiles leave the hull of a ship intact, they are often used as a "less lethal" option when a ship needs to be disabled without killing the crew or rendering the ship unsalvageable. Using HARMs is a good way to capture a ship relatively intact, provided the crew values their lives.