A tangent section is shown after the build section. The purpose of thetangent is to maintain angle and direction until the next target is reached. Inthe example well, a drop section is shown at the end of the tangent. Thepurpose of a drop is usually to place the wellbore in the reservoir in theoptimum orientation with respect to formation permeability or in-situformation stress; alternatively, a horizontal extension may be the preferredorientation in the case of a pay-zone that contains multiple vertical fracturesor that has potential for gas or water coning.