• Spray Zone: receives some splash from crashing waves at high tide, lichens are found here
• Upper Intertidal: covered only during the high tide, blue-green algae are present here
• Mid-Intertidal: submerged and exposed during each tide, you'll find barnacles here
• Lower Intertidal: exposed briefly at low tide, brown algae and mussels like it here
• Subtidal: an area of high wave activity at low tide, always submerged, where you'll find kelp

Not all rocky shores look like this one. The geology of intertidal areas range from long stretches of solid rock and ledge like the one seen above to...