A targeting scanner (or target acquisition) is a part of the transporter system. It is used to locate objects which need to be transported.
Targeting scanners can also be used to aim weapons at a target, during a tactical scenario. In an alternate version of 1944, Armory officer Malcolm Reed attempted to use the targeting scanners aboard the NX-class starship Enterprise to destroy a facility belonging to Vosk, the leader of the Na'kuhl. He was unable to lock on to the building with targeting scanners, so he used visual scanners instead. (ENT: "Storm Front, Part II")