The Pacific shore in this photo is a place of wave erosion. The surf pounds the cliffs and breaks them, washing their pieces offshore in the form of sand and pebbles. Slowly the sea pushes into the land, but its erosion cannot extend downward beyond the bottom of the surf zone. Thus the waves carve out a fairly level surface offshore, the wave-cut platform, divided into two zones: the wave-cut bench at the foot of the wave-cut cliff and the abrasion platform farther from shore. The bedrock knobs that survive on the platform are called chimneys. See more of these features in the wave-cut platform gallery.
Tectonically active coasts, like that of California, commonly rise and bring the wave-cut platform above the sea. Thus we have here an active wave-cut platform in the foreground and an older, fossil platform in the background. Some places have as many as a dozen of these, stepping up the coastal mountainsides, where they are commonly called wave-cut terraces. But careful users of geologic terms reserve "terrace" for a platform that is built up by deposition rather than carved by erosion. The strandline features around lakes are examples.