This topic defines porosity and describes its different types as they relate to reservoir quality. It defines permeability and explains how it is determined in a laboratory setting. The course summarizes the different elements associated with rock texture and describes how those elements affect the porosity and permeability of a reservoir. It explains how capillary pressure affects the overall quality of a reservoir. The four sandstone burial factors that affect porosity and permeability and the three main cementation types that degrade porosity in sandstones are described. The course explains the ways in which porosity can be degraded in limestones and dolomites. It identifies the rocks that typically form atypical reservoirs and how porosity primarily occurs in these reservoirs. The differences between pay, net pay and gross pay, and how reservoir formations can affect these calculations are described. The five different types of reservoir shapes associated with areal continuity and the different types of reservoir orientations associated with cross-sectional continuity are explained. The course describes how to calculate a reservoir’s initial oil and gas in-place volume using basic inputs and equations.