The purpose of this book is to introduce readers to the science of this type of drilling. Readers will learn the types and uses of directional holes, how a well is planned, what information and equipment are needed, and some of the problems associated with directional drilling. This lesson assumes that workers are already familiar with basic drilling procedures and terms. Detailed descriptions and illustrations help demonstrate concepts outlined in the pages that follow. A conversion table is available in the front of the book to help interpret standard and metric units of measurement.