In this and the following two chapters a description is given of the intertidal areas around the world, subdivided into macro-, meso-, and microtidal areas. They form the basis for the more process-oriented Chapters 6 through 9. The wind flat areas, where the tidal range is small but onshore winds can raise the water level one or two meters (with extensive flooding where the coastal area is flat), are described in Chapter 5. This chapter is concerned with macrotidal areas.