Directional boring, also referred to as horizontal directional drilling which is HD Drilling, is a minimal impact trenchless method of installing underground utilities such as pipe, conduit, or cables in a relatively shallow arc or radius along a prescribed underground path using a surface-launched drilling rig. Horizontal Directional Drilling (HDD) is a method of installing underground pipelines, cables and service conduit through trenchless methods. It involves the use of a directional drilling machine, and associated attachments, to accurately drill along the chosen bore path and back ream the required pipe.
Directional Drilling is the process of drilling which controls the direction and deviation of the boring programmed to the targeted location. Horizontal Drilling is the process of drilling where the direction of the well is horizontal.