An Introduction to Geology book gives the basic concepts of geology by appreciating the formation and modification of the planet Earth on which we live. Apart from explaining geological and engineering principles' practice in industry with emphasis on exploration and exploitation of mineral resources, geohazards' scenarios of historical significance, geology plays an important role in designing foundations for structures such as dams and bridges. The main geological background knowledge of the book is provided in chapters on mineralogy, petrology for igneous, sedimentary and metamorphic rocks, weathering and structural geology. Provision of labelled illustrations, as is expected for technical textbooks, including labelled images so as to fully benefit the reader has been addressed. Evaluation aspects and exercises are provided at the end of each chapter while considering competencies that were adduced at the beginning of each chapter as a new approach for authorship of education material. In addition, glossary with an illustrated narrative summary for each chapter further strengthens the reader's perception of geological realities in a competency based approach.